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UNIVERSITY    OF    CALIFORNIA    PUBLICATIONS 

BULLETIN    OF  THE    DEPARTM  ENT.  OF 

GEOLOGY 

Vol.  7,  No.  5,  pp.  61-115  Issued  October  12,  1912 


CONTRIBUTIONS   TO   AVIAN    PALAEON- 
TOLOGY FROM  THE   PACIFIC   COAST 
OF   NORTH  AMERICA 


BY 

LOYE    HOLMES    MILLER 


UNIVERSITY  OF  CALIFORNIA  PRESS 
BERKELEY 


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1.  The  Geology  of  Point  Sal,  by  Harold  W.  Fairbanks ," 65c 

2.  On  Some  Pliocene  Ostracoda  from  near  Berkeley,  by  Frederick  Chapman lOc 

3.  Note  on  Two  Tertiary  Faunas  from  the  Rocks  of  the  Southern  Coast  of  Vancouver 

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on  the  Classification  of  the  Neocene  Formations,  by  John  C.  Merriam lOc 

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11.  Contributions  to  the  Mineralogy  of  California,  by  Walter  C.  Blasdale 15c 

1 2.  The  Berkeley  Hills.     A  Detail  of  Coast  Range  Geology,  by  Andrew  C.  Lawson  and 

Charles  Palache  80c 

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2.  Colemanite  from  Southern  California,  by  Arthur  S.   Eakle : 15c 

3.  The   Eparchaean   Interval.     A   Criticism  pf.the  use   of  the  term   Algonkian.  by 

Andrew  C.  Lawson  ./...".. -V .*.**. •..*.i?\.«...Jl lOc 

4.  Triassic  Ichthyopterygia  ifom  ©aliforma?  £»cl  Nevada,  by  John  C.  Merriam 50c 

6.  The  Igneous  Rocks. n^aj-  Pa^jarQ,  Jjy  .John  .A.* -Reid 15c 

7.  Minerals  from  Leo£k  Ke^gl^3,;A4arra5da:Girv  California,  by  Waldemar  T.  Schaller     15c 
3.  Plumasite,    an    Oligo'cla'se-Cofuridum "  <E?<5c*k",  *  n'ear    Spanish    Peak,    California,    by 

Andrew  C.  Lawson  .'..     lOc 

9.  Palacheite,  by  Arthur  S.  Eakle : ]0c 

10.  Two  New  Species  of  Fossil  Turtles  from  Oregon,  by  O.  P.  Hay. 

11.  A  New  Tortoise  from  the  Auriferous  Gravels  of  California,  by  W.  J.  Sinclair. 

Nos.  10  and  11  in  one  cover lOc 

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13.  Spodumene  from  San  Diego 'County,  California,  by  Waldemar  T.  Schaller lOc 

14.  The   Pliocene    and    Quaternary    Canidae    of   the    Great    Valley    of   California,   by 

John  C.  Merriam  15c 

T.5.  The  Geomorphogeny  of  the  Upper  Kern  Basin,  by  Andrew  C.  Lawson 65c 

16.  A  Note  on  the  Fauna  of  the  Lower  Miocene  in  California,  by  John  C.  Merriam 5c 

17.  The  Orbicular  Gabbro   at  Dehesa,  San  Diego   County,  California,  by  Andrew  C. 

Lawson      lOc 

18.  A  New  Cestraciont  Spine  from  the  Lower  Triassic  of  Idaho,  by  Herbert  M.  Evans  lOc 

19.  A  Fossil  Egg  from  Arizona,  by  Wm.  Conger  Morgan  and  Marion  Clover  Tallmon  lOc 

20.  Euceratherium.   a   New  Ungulate   from   the   Quaternary   Caves   of   California,   by 

William  J.  Sinclair  and  E.  L.  Furlong , lOc 

21.  A  New  Marine  Reptile  from  the  Triassie  of  California,  by  John  C.  Merriam  5c 

22.  The  River  Terraces  of  the  Orleans  Basin,  California,  by  Oscar  H.  Hershey 35c 


UNIVERSITY  OF  CALIFORNIA   PUBLICATIONS 

BULLETIN    OF    THE    DEPARTMENT    OF 

GEOLOGY 

Vol.  7,  No.  5,  pp.  61-115  Issued  October  12,  1912 


CONTRIBUTIONS  TO  AVIAN  PALAEONTOL- 
OGY FROM  THE  PACIFIC  COAST 
OF  NORTH  AMERICA 

BY 

LOYE  HOLMES  MILLEE 


CONTENTS 

PAGE 

Introduction    62 

Acknowledgments  62 

Significance  of  Osteological  Characters  in  Ornithology  63 

Review  of  the  Literature 64 

Material  available  66 

Oligocene  Fauna 66 

Miocene  Fauna  67 

Pleistocene   Fauna   68 

Potter  Creek  Cave  ! :::.. 68 

Samwel  Cave    71 

Hawver  Cave  -  - 73 

Eancho  La  Brea  75 

Fossil  Lake    78 

Rodeo  Pleistocene  82 

Present  Physiographic  and  Geographic  Relations  of  the  West-American 

Regions  in  which  Fossil  Avian  Remains  are  known  82 

Relation  of  Pleistocene  Faunas  to  those  of  the  Present  Day  84 

Distribution  of  the  Cathartidae  85 

Distribution  of  the  Falconidae  92 

Anomalies  in  Distribution  96 

Possible  Influences  Conditioning  Present  Distribution  of  Certain 

Groups  102 

Bird  Remains  as  Indicators  of  Climatic  Conditions  103 

Time  Relations  as  Suggested  by  a  Study  of  Bird  Remains  105 

Causes  of  Extinction  of  Birds  108 

Tabular  Arrangement  of  West-American  Pleistocene  Avifaunas  112 

Bibliography  of  Pacific  Coast  Fossil  Avifaunas  115 


244558 


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*.*  '•<  •/ •  V*  •  .    •  •     •  *•««  j  • 

•  *•«•*••*•          •   «••••      •• 

62  University  of  California  Publications  in  Geology     [VOL.  7 


INTRODUCTION 

When  the  vertebrate  palaeontologist  turns  his  attention  to 
the  group  Aves  as  represented  in  North  America,  especially  if 
he  be  confronted  with  the  problems  represented  by  a  considerable 
mass  of  unassorted  material,  he  cannot  but  feel  that  he  pushes 
out  into  almost  uncharted  waters,  a  wide  sea  where  the  few 
islands  recorded  by  previous  explorers  —  islands  too  often 
shrouded  in  mist — may  perhaps  never  appear  upon  his  horizon. 
The  scarcity  of  previous  record,  the  wide  separation  in  place  of 
the  bird-bearing  deposits,  coupled  with  the  inadequacy  of  descrip- 
tions and  the  poverty  of  museums  in  collections  of  Recent  avian 
osteology — rail  these  are  factors  which  conspire  to  give  the  student 
entering  upon  such  an  undertaking  the  feeling  that  he  stands 
or  falls  unto  himself.  In  full  cognizance  of  these  conditions  the 
present  paper  is  undertaken.  Its  dual  purpose  is  the  recording 
of  certain  facts  but  recently  made  known  in  this  interesting  field, 
and  the  correlating,  insofar  as  this  is  possible,  of  the  results  thus 
far  attained. 

ACKNOWLEDGMENTS 

Study  of  the  University  of  California  collections  was  taken 
up  at  the  invitation  of  Professor  John  C.  Merriam,  head  of 
the  Department  of  Palaeontology  of  that  institution,  and  to  his 
unstinted  aid,  encouragement,  and  advice  much  of  what  value 
this  study  may  possess  is  here  freely  ascribed.  Grateful  acknowl- 
edgement is  also  made  to  Messrs.  Joseph  Grinnell  and  H.  S. 
Swarth  of  the  California  Museum  of  Vertebrate  Zoology  for 
information  cheerfully  furnished  on  many  Recent  species  and 
for  the  loan  of  osteological  material.  Specimens  of  great  interest 
and  value  were  loaned  or  donated  by  Dr.  F.  A.  Lucas,  Dr.  A. 
Smith- Woodward,  Dr.  F.  C.  Clark,  Dr.  C.  O.  Esterly,  Mr.  E.  J. 
Fischer,  and  Mr.  J.  Z.  Gilbert.  The  very  generous  attitude  taken 
by  Madam  Ida  Hancock-Ross  and  the  associated  owners  of 
Rancho  La  Brea  in  issuing  permits  to  excavate  the  asphalt  de- 
posits made  possible  the  assembling  of  much  valuable  material 
essential  to  the  work.  Through  the  personal  efforts  of  Dr.  J.  C. 
Hawver,  of  Auburn,  California,  as  well  as  by  the  very  cordial 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  63 

assistance  extended  by  him  to  the  author,  our  knowledge  of  the 
Hawver  Cave  deposits  has  been  greatly  advanced.  To  each  of 
these  persons  the  author's  sincere  thanks  are  extended. 

SIGNIFICANCE   OF   OSTEOLOGICAL   CHARACTERS   IN   ORNITHOLOGY 

In  a  zoological  group  of  such  narrow  delineation  and  of  such 
great  homogeneity  as  the  class  Aves,  where  separation  into  the 
various  systematic  divisions  is  based  upon  relatively  small  varia- 
tions and  where  these  variations  affect  structures  not  preserved 
for  study,  a  considerable  degree  of  care  must  be  exercised  when 
interpreting  discoveries  of  the  palaeontologist  in  terms  of  modern 
systematic  zoology.  The  difference  noticeable  to.  a  worker  in  the 
former  field  should  in  many  cases  be  multiplied  by  a  very  large 
factor  upon  their  transposal  to  the  latter.  Degrees  of  diver- 
gence which  to  the  palaeontologist  seem  of  no  more  than  specific 
rank  might,  by  the  worker  in  systematic  ornithology,  having 
also  various  intricate  details  of  color-pattern  or  feather  struc- 
ture at  his  disposal,  be  found  correlated  with  differences  of 
more  than  generic  importance.  The  distinction  upon  osteological 
characters  of  many  well-defined  species  of  Recent  birds  is  a 
matter  requiring  complete  skeletons  of  individuals  of  known  sex ; 
even  then  conclusions  are  often  in  question.  It  is  here  con- 
ceded as  possible  under  these  conditions,  and  considering  the 
fact  that  most  of  the  fossil  specimens  are  not  capable  of  articula- 
tion, that  many  of  the  fossil  specimens  ascribed  to  living  species 
might,  if  all  characters  were  determinable,  be  separated  as  dis- 
tinct forms.  It  must  be  remembered  also  that  within  certain 
groups  the  osteological  differences  between  species  is  greater  than 
in  others.  The  feather  of  the  bird  is  an  epidermal  structure 
which  reflects  with  sensitiveness  the  activities  of  the  animal  and 
is  plastic  as  a  specific  character  under  the  influences  of  environ- 
mental changes.  It  is  a  proper  basis  of  specific  distinction,  yet 
it  is  almost  never  preserved  in  the  fossil  state.  The  tooth  of 
the  mammal,  likewise  an  epidermal  structure  and  highly  repre- 
sentative of  the  animal's  activities,  is  a  character  used  in  com- 
mon by  the  palaeontologist  and  the  modern  systematist.  Zoology 
and  palaeontology  are  then  much  more  nearly  upon  the  same 


64  University  of  California  Publications  in  Geology     [VOL.  7 

basis  in  the  determination  of  mammals  than  is  the  case  with 
birds.  Recognizing  this  principle,  the  author  of  this  paper  has 
proceeded  with  perhaps  more  than  necessary  caution  in  the  an- 
nouncement of  new  species,  preferring  to  err  on  the  part  of 
conservatism  rather  than  to  confuse  the  literature  of  the  subject 
by  making  assertions  which  must  later  be  modified ;  and  there  are 
in  the  collections  studied  many  specimens  regarding  which  fur- 
ther knowledge  is  considered  necessary  before  problems  upon 
which  they  may  throw  light  can  be  attacked  in  more  than  a 
speculative  way. 

REVIEW  OF  THE  LITERATURE 

Since  the  epoch-making  discoveries  by  Marsh  which  added 
so  materially  to  our  conception  of  the  ancestry  of  birds,  con- 
tributions to  knowledge  in  the  field  of  avian  palaeontology  have 
been  few  as  compared  with  the  rapid  enlargement  of  our  under- 
standing of  the  other  vertebrate  groups.  Bird  remains  on  the 
Pacific  Coast  are  mainly  from  Pleistocene  strata;  thus  there  is 
eliminated  the  probability  of  shedding  much  new  light  upon  the 
ancestry  of  certain  groups  in  which  our  interest  is  so  acutely 
focused,  for  example  the  Stereornithes.  Discoveries  recently 
made  have  contributed  to  science  chiefly  in  two  ways,  first  in 
giving  us  an  appreciation  of  the  relative  antiquity  of  the  main 
groups  into  which  birds  are  divided;  and,  second,  in  adding  to 
our  knowledge  of  the  geographical  distribution  of  these  groups. 
The  consideration  of  geographical  distribution  is  but  begun  when 
we  record  the  range  of  the  Recent  species.  Determination  of 
the  factors  which  have  led  to  such  distribution,  if  we  aspire  to 
something  better  than  mere  speculation,  must  look  to  the  record 
of  previous  conditions  as  brought  to  light  through  palaeontol- 
ogical  inquiry. 

The  fossil-bearing  rocks  of  the  Pacific  Coast  of  North 
America,  while  rich  in  the  remains  of  mammals  and  reptiles, 
have  until  recently  yielded  but  little  information  concerning  the 
avian  group. 

In  1878,  Cope1  described  three  new  species  of  birds  from 
the  Equus  Beds  of  Oregon.  All  three  species  belong  to  genera 


i  Cope,  E.  D.,  Bull.  U.  S.  G.  S.,  Terr.,  iv,  No.  2,  May  3,  1878. 


1912 J  Miller:  Pacific  Coast  Avian  Palaeontology  65 

still  inhabiting  the  region;  thus  their  importance  is  limited  to 
the  evidence  they  furnish  of  the  division  of  a  genus  into  several 
coordinate  species. 

In  1892,  Shufeldt2  published  the  results  of  an  extended  study 
of  the  Cope  and  the  Condon  collections  of  birds  from  this  same 
region.  In  this  very  thorough  discussion  there  are  fifty  species 
enumerated,  fourteen  of  which  are  described  as  new.  The  entire 
number,  with  the  exception  of  the  gallinaceous  Paleotetrix  gilli, 
are  assigned  to  existing  genera.  Phoenicopterus  is  the  only 
existing  genus  recorded  which  is  foreign  to  the  region  at  present. 

In  1894,  Cope3  described  a  single  species,  Cyphornis  magnus, 
from  a  formation  in  Vancouver,  British  Columbia,  which  he 
placed  with  some  reservation  in  the  Eocene,  but  which  was  later 
considered  by  others  to  be  Oligocene.  The  species  is  considered 
as  pelecanid  in  its  affinities  but  generically  distinct  from  any 
form  now  living. 

Lucas,  in  1901, 4  described  a  new  genus  and  species  of  diver, 
Mancalla  calif  orniensis,  from  a  formation  at  Los  Angeles,  Cali- 
fornia. From  the  associated  invertebrate  fauna,  this  species  is 
considered  by  Dall  to  be  of  upper  Miocene  or  lower  Pliocene  age. 

As  a  result  of  the  preliminary  study  put  upon  the  University 
of  California  collections  by  the  present  writer,  there  have  ap- 
peared a  series  of  short  papers  dealing  with  a  number  of  species 
from  Fossil  Lake,  Oregon,  and  from  the~~caverns  and  the  asphalt 
beds  of  California.  While  these  papers  record  one  unique  form, 
Teratornis,  of  unusual  interest,  the  main  value  of  the  contribu- 
tions, like  that  of  Shufeldt 's,  lies  in  the  light  shed  upon  the 
former  distribution  of  families  of  birds  still  living.5 


2  Shufeldt,  E.  W.,  Journ.  Acad.  Nat.  Sci.  Phila.,  Ser.  2,  No.  9,  p.  389, 
1892. 

s  Cope,  E.  D.,  Journ.  Acad.  Nat.  Sci.  Phila.,  Ser.  2,  No.  9,  p.  449,  1894. 

*  Lucas,  F.  A.,  Proc.,  U.  S.  Nat.  Mus.,  vol.  24,  p.  133,  1901. 

s  Miller,  L.  H.,  Univ.  Calif.  Publ.,  Bull.  Dept.  Geol.,  vols.  5-6  passim, 
1909-11. 


66  University  of  California  Publications  in  Geology     [VOL.  7 

MATERIAL  AVAILABLE 

The  material  upon  which  studies  of  the  west  coast  fossil 
birds  have  been  based  has  been  collected  from  nine  different 
horizons,  summarized  as  follows : 

OLIGOCENE 

Vancouver,  B.C.     One  species  (a  single  specimen). 
MIOCENE 

Virgin  Valley  Beds,  Virgin  Valley,  Nevada.     One  species. 

Los  Angeles,  California.     One  species   (a  single  specimen). 
PLEISTOCENE 

Potter  Creek  Cave,  California.     Sixteen  species. 

Samwel  Cave,  California.     Nineteen  species. 

Hawver  Cave,  California.     Twelve  species. 

Eodeo  Pleistocene,  California.    One  species  (a  single  specimen). 

Eancho  La  Brca,  California.     Forty-nine  species. 

Fossil  Lake,  Oregon.     Fifty-three  species. 

The  avian  collections  assembled  at  the  University  of  Cali- 
fornia represent  seven  of  these  localities.  One  of  the  seven  is 
identical  with  that  studied  by  Cope  and  Shufeldt,  namely,  the 
Fossil  Lake  region  of  Oregon.  The  remaining  six  collections,  so 
far  as  known  to  the  writer,  have  not  been  studied  previous  to 
the  assumption  of  the  task  here  in  part  recorded.  Three  or 
four  hundred  specimens  represent  the  bird  remains  from  the 
caves,  and  three  or  four  thousand  have  been  taken  from  the 
asphalt  at  Rancho  La  Brea. 

So  far  as  can  be  learned,  the  Oligocene  horizon  yielding 
Cyphornis  to  Cope,  and  the  Miocene,  from  which  Lucas  described 
Mancalla,  have  yielded  no  other  avian  fossils. 

OLIGOCENE  FAUNA 

Cyphornis  magnus  Cope  is  the  only  species  known  to  the 
coast  from  strata  of  possibly  so  great  age.  The  form  was  de- 
scribed by  Cope6  from  a  single  specimen,  the  proximal  end  of 
a  tarsometatarsus,  the  property  of  the  Geological  Survey  of 
Canada.  The  osteological  characters  displayed  by  the  speci- 
men are  such  as  to  have  led  Cope  to  assign  the  species 
with  some  reserve  to  the  family  Pelecanidae. «  Interest 
centers  to  some  extent  in  a  combination  of  the  two  characters, 


e  Cope,  E.  D.,  Journ.  Acad.  Nat.  Sci.,  Phila.,  Ser.  2,  No.  9,  p.  449.  ]894. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  67 

large  size  and  high  degree  of  pneumaticity.  The  latter  character 
was  considered  by  the  author  of  the  species  as  indicating  the 
bird's  ability  to  fly.  If  such  conclusion  be  true,  the  species,  since 
the  tarsometatarsus  equaled  in  size  that  of  the  rhea,  must  be 
considered  as  the  largest  known  flying  bird. 

It  may  not  be  out  of  place  here  to  consider  the  propriety  of 
Cope's  position  regarding  the  relation  of  pneumaticity  to  the 
power  of  flight.  Let  it  be  conceded  that  Cyphornis  belonged  to 
the  Pelecanidae,  birds  of  large  size  which  are  possessed  of  a 
high  degree  of  pneumaticity.  We  may  then  ask  if  the  char- 
acter pneumaticity  necessarily  became  vestigial  or  disappeared 
with  the  loss  of  ability  to  fly  resulting  from  increased  size.  The 
development  of  such  a  character  as  gigantism  might  be  a  matter 
of  comparatively  short  time,  while  the  persistence  of  the  char- 
acter pneumaticity  might  be  very  tenaceous.  An  instructive  case 
in  point  is  that  of  Geococcyx,  a  cuckoo  of  terrestrial  habit  whose 
powers  of  flight  have  been  almost  entirely  sacrificed.  The  pec- 
toral arch  in  this  bird  is  an  absurdly  weak  structure,  while 
there  is  an  accompanying  accentuated  development  of  the  pos- 
terior limb  region.  Despite  this  inversion  of  the  appendicular 
parts,  the  skeleton  remains  highly  pneumatic.  It  seems  well 
within  the  range  of  possibility  that  Cyphornis  should  have 
gained  its  large  size  by  a  rapid  specialization — a  tendency  run 
riot  under  certain  conditions  not  adverse  to  it — and  yet  this 
specialization  cost  the  bird  its  power  of  flight  without  blotting 
out  the  character  of  pneumaticity. 

MIOCENE  FAUNA 

Mancalla  calif  or  niensis  Lucas,  from  the  upper  Miocene  of 
Los  Angeles,  California,  is  described  by  Lucas7  as  being  much 
like  the  Recent  species  of  murre  (Uria  troille)  of  that  region,  but 
more  highly  specialized  in  that  it  was  probably  without  the  power 
of  flight.  The  single  specimen  known  consists  of  the  major  part 
of  the  left  humerus  of  a  bird  about  the  size  of  the  recently 
extinct  great  auk  (Plaurus  impennis).  Interest  in  this  discov- 
ery lies  largely  in  the  strong  similarity  of  the  bird  to  Recent 


7  Lucas,  F  A.,  Proc.  U.  S.  Nat.  Mus.,  vol.  24,  p.  133,  1901. 


68  University  of  California  Publications  in  Geology     LV°L-  7 

forms,  in  its  flightless  character  suggesting  to  the  author  of  the 
species  an  insular  breeding-ground  free  from  enemies,  and 
finally  in  the  fact  that  the  accompanying  molluscan  fauna  in- 
dicates a  climate  cooler  than  that  which  characterizes  the  region 
at  present.  It  is  regretable  that  a  larger  number  of  species  was 
not  discovered  in  the  same  horizon. 

PLEISTOCENE   FAUNA 

Potter  Creek  Cave. — Potter  Creek  Cave8  takes  its  feiame 
from  its  location  on  Potter  Creek,  about  one  mile  east  of  Baird, 
a  station  of  the  U.  S.  Bureau  of  Fisheries  on  the  McCloud  River 
in  Shasta  County,  California.  The  locality  lies  at  present  in 
the  lower  Transition  zone  at  an  elevation  of  1500  feet  above  the 
sea.  The  surrounding  country  is  well  timbered  with  conifers, 
oaks,  and  maples  in  the  main,  and  with  lower  scrub  forming 
thickets  in  less  favorable  exposure.  Topographically  the  region 
is  rendered  rather  rough  by  numerous  small  tributaries  of  the 
McCloud  River  cutting  through  the  Baird  Shales,  and  the 
McCloud  Limestones,  to  form  canons  with  abrupt  slopes  and 
much  dissected  ridges.  The  cave  occupies  at  present  a  position 
800  feet  above  the  McCloud  River,  only  slightly  over  a  mile  away. 

According  to  the  observations  of  Sinclair,  the  river  flowed 
during  the  formation  of  the  cavern  deposits  at  approximately 
the  level  of  the  cave  floor.  The  lowering  of  the  river  bed  and 
the  backward  cutting  of  tributary  streams  brought  about  more 
rapid  drainage  of  the  country  to  either  side  of  the  cave,  less 
water  entered  the  fissure,  and  cave-cutting  ceased.  Openings 
were  formed  later  in  the  roof  of  the  cave  by  surface  erosion, 
thus  permitting  the  entrance  of  clay,  rock  fragments,  broken 
bones  and  possibly  of  live  animals.  Subsequent  uplift  increased 
the  cutting  by  streams  in  the  region,  and  Potter  Creek  cut 
down  through  one  of  the  galleries,  thus  forming  the  present  cave 
entrance. 

There  were  two  or  three  of  these  periods  of  uplift  as  deter- 
mined by  Sinclair  which  changed  the  character  of  the  country 
from  one  of  moderate  relief  to  one  of  mountainous  aspect  dis- 


s  See  Sinclair,  W.  Jv  Univ.  Calif.  Publ.   Am.   Arch.   Ethn.,  vol.   2,  pp. 
1-27,  1904. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  69 

sected  by  river  canons.  The  indications  are  that  the  actual 
elevation  at  present  is  considerably  greater  than  that  during  the 
deposition  of  the  bone-bearing  material.  Certainly  the  relation 
of  the  cave  to  the  river  level  has  changed  in  the  neighborhood  of 
eight  hundred  feet.  There  is  no  evidence  of  a  later  subsidence 
noted,  so  we  may  assume  that  the  conditions  during  the  period 
of  deposition  were  more  like  those  at  Rancho  La  Brea  than  they 
are  at  present,  i.e.,  less  abrupt  elevation  and  a  smoother  top- 
ography. The  presence  of  Dendragapus  in  the  cave  deposits  is 
an  indication,  however,  that  conditions  were  not  identical  in 
the  two  localities. 

A  very  interesting  description  of  the  various  chambers  and 
galleries  of  the  cavern  is  given  in  Sinclair's  paper.  The  fossil- 
bearing  matrix  represents  the  accumulation  on  the  floors  of  the 
chambers  and  pockets  in  the  form  of  fans  of  detritus,  admitted 
doubtless  through  old  chimney-like  chutes  now  entirely  blocked 
by  limestone  accretions  and  washed  debris.  These  fans  of  ac- 
cumulated material  were  encrusted,  and  in  some  instances 
cemented,  by  stalagmitic  deposits  so  that  blasting  had  to  be  re- 
sorted to  in  places. 

The  remains  are  in  most  cases  entirely  dissociated.  Sinclair 
notes  the  finding  of  a  few  skeletons  in  their  proper  anatomical 
relations,  such  as  those  of  a  squirrel,  a  woodrat,  a  snake,  and  a 
bat.  These  are  all  animals  which  would  go  into  caves  of  their 
own  accord  and  after  death  fall  upon  the  floors  of  the  caverns. 
No  case  of  bird  skeletons  in  any  degree  associated  is  to  be  found. 
The  bones  have  entirely  lost  their  organic  matter  and  appear 
almost  as  though  calcined.  Perfect  bones  of  the  smaller  verte- 
brates are  rare.  In  most  cases  fracture  has  occurred  and  in 
many  the  articular  surfaces  have  been  injured,  either  on  account 
of  the  delicacy  of  the  cancellated  bone  in  that  region,  or  because 
the  presence  of  articular  cartilages  tempted  the  appetites  of 
gnawing  forms.  Weathering  and  cracking  due  to  exposure  on 
the  surface  is  the  only  reasonable  explanation  of  the  imperfec- 
tions of  some  specimens. 

Sinclair  suggests  three  methods  of  possible  introduction  of 
animal  remains  into  the  cave.  Washing  by  rills  which  carried 
bones  from  the  surface  down  by  way  of  the  nearly  vertical  chim- 


70 


University  of  California  Publications  in  Geology     ITOL-  7 


neys  seems  a  very  probable  method.  These  open  chimneys  may 
have  acted  as  pitfalls  into  which  animals  blundered  in  passing 
over  the  surface.  Again,  predatory  forms  may  have  carried 
their  prey  into  the  mouths  of  the  caverns  whence  the  accumulated 
bones  were  washed,  or  carried  by  woodrats,  into  the  more  remote 
recesses.  This  last  method  seems  to  the  present  author  the 
most  probable  means  of  introduction  of  such  forms  as  the 
anserines  among  birds.  Falco  peregrinus,  whose  remains  also 
occur  in  the  deposits,  is  a  large  and  powerful  hawk  which 
habitually  resorted  to  such  places  to  nest.  About  the  entrances 
to  their  nesting  crevices  today  one  commonly  finds  the  ac- 
cumulated bones  of  a  great  variety  of  vertebrates  brought  as 
prey.  Their  predilection  for  the  anserines  has  given  these  birds 
their  common  name  of  duck  hawk. 

Sinclair  records  the  following  list  of  vertebrates  from  the 
Potter  Creek  Cave  deposits,  marking  extinct  species  with  an 
asterisk : 

SINCLAIR'S  LIST  OP  SPECIES  FROM  POTTER  CREEK  CAVE 


*Arctotherium  simum  Cope. 
*Ursus,  n.  sp. 
*Felis,  n.  sp. 

Felis,  near  hippolestes  Merriam, 
C.  H. 

Lynx  fasciatus  Rafinesque. 

Lynx  fasciatus,  n.  subsp.  (?) 

Urocyon  townsendi  Merriam,  C.  H. 

Vulpes  cascadensis  Merriam,  C.  H. 
*Canis  indianensis  Leidy. 
*Taxidea,  n.  sp*. 

Bassariscus  raptor  Baird. 

Mephitis  occidentalis  Baird. 
*Spilogale,  n.  sp. 

Putorius  arizonensis  Mearns. 

Arctomys,   sp. 

Sciurus    hudsonicus    albolimbatus 
Allen. 

Sciuropterus     klamathensis     Mer- 
riam, C.  H. 

Spermophilus     douglasi     Richard- 
son. 

Eutamias  senex   (?)   Allen. 


Callosp'ermophilus    chrysodeirus 
Merriam,  C.  H. 

Lepus  californicus  Gray. 

Lepus    klamathensis    Merriam,    C. 
H. 

Lepus,  near  auduboni  Baird. 

Lepus,  sp. 
*Teonoma,  n.  sp. 

Neotoma  fuscipes  Baird. 

Microtus  californicus  Peale. 
*Thomomys,  n.  sp. 

Thomomys  leucodon  Merriam,  C. 
H. 

Thomomys  monticola  Allen 
*Aplodontia  major,  n.  subsp. 

Scapanus  californicus    (?)   Ayres. 

Antrozous  pallidus  Merriam,  C.  H. 
*Platygonus    (?)    sp. 

Odocoileus,  sp.  a. 

Odocoileus,  sp1.  b. 

Haplocerus  montanus  Ord. 
*Euceratherium    collinum    Sinclair 
and  Furlong. 


*  Species   marked  with   the  asterisk    (*)    are   either   extinct   or   are   no 
longer  represented  in  the  region. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  71 

*Bison,  sp.  *Equus  occidentalis  Leidy. 

*Camelid.  *Equus   pacificus  Leidy. 
*Megalonyx  wheatleyi  (?)  Cope.  Crotalus,  sp. 

*Megalonyx    jeffersonii    (?)    Har-  Mylopharadon  conocephalus  Baird 

Ian.  and  Gerard. 

*Megalonyx,  n.  sp.  Ptychocheilus     (?)     grandis     (?) 

*Megalonyx,  sp.  (Ayres). 

*  Mastodon  americanus  Kerr.  Acipenser  medirostris    (?)    Ayres. 

*Elephas  primigenius  Blumb. 

To  this  list  of  species  published  by  Sinclair,  the  studies  of  the 
present  author9  would  add  the  following  birds : 

SPECIES  OF  BIRDS  FROM  POTTER  CREEK  CAVE 

Branta  canadensis   (Linnaeus).  *Catharista  shastensis  Miller. 

Oreortyx  picta  (Douglas).  Buteo  borealis  (Gmelin). 

Dendragapus  obscurus    (Say).  Falco  peregrinus  Tunstall. 

*Bonasa  umbellus  (Linnaeus).  Falco  sparverius  Linnaeus 

Indeterminate   odontophorid.  Otus  asio  (Linnaeus). 

*Meleagris,  sp.  *Bubo  sinclairi  Miller. 
*Gymnogyps  amplus  Miller.  Colaptes  cafer    (Gmelin). 

Cathartes  aura   (Linnaeus).  Corvus  brachyrhynchos  Brehm. 

*  Species  marked  with  the  asterisk  (*)  are  either  extinct  or  are  no 
longer  represented  in  the  region. 

Samivel  Cave. — Samwel  Cave  was  explored  by  E.  L.  Fur- 
long, then  of  the  University  of  California,  who  published  an 
account  of  his  work  two  years  after  the  appearance  of  Sinclair's 
paper  on  the  Potter  Creek  Cave.  Furlong's  account10  pictures 
a  cavern  not  essentially  different  from  that  described  by  Sin- 
clair. The  conditions  of  interment  seem  to  have  been  somewhat 
different,  however,  since  there  occurred  a  number  of  entire  skele- 
tons of  large  and  small  carnivores  and  one  form  of  ungulate, 
Preptoceras,  which  were  preserved  without  fracture  of  the  bones 
and  in  the  proper  anatomical  relation.  Furlong  reaches  the 
conclusion  that  the  cavern  was  used  as  a  lair  by  such  forms  as 
the  bear  and  the  cougar.  To  this  lair  the  bodies  of  larger 
ungulates  like  Euceratherium  and  Preptoceras  were  dragged  as 
prey.  Some  of  the  carcasses  were  left  almost  entire  while  others 
were  torn  to  pieces  and  the  bones  more  or  less  broken  by  the 


»  Miller,  L.  H.,  Univ.  Calif.  Publ.,  Bull.  Dept.  Geol.,  vol.  6,  p.  385,  1911. 
10  Furlong,  E.  L.,  Am.  Journ.  Sci.,  vol.  22,  pp.  235-247,  Sept.,  1906. 


72  University  of  California  Publications  in  Geology     [V°L-  " 

teeth  of  the  captor.  The  suggestion  is  also  made  that  the  cavern 
may  have  been  used  as  a  den  for  hibernation  by  various  ursines, 
even  as  other  caverns  in  the  region  are  known  to  be  used  by 
bears  of  today. 

No  specimen  of  bird  skeleton  was  found  with  bones  in  proper 
place,  so  the  probability  is  that  the  remains  representing  this 
class  were  introduced  largely  as  in  the  case  of  the  Potter  Creek 
Cave  specimens.  Some  essential  difference  must  have  existed, 
however,  since  the  relation  in  numbers  of  the  different  species  is 
so  different  in  the  two  localities.  The  Cathartiformes  appear  in 
Potter  Creek  Cave  represented  by  forty-five  specimens  distri- 
buted over  three  species.  In  Samwel  Cave  there  appear  but  six 
specimens  possibly  assignable  to  the  group.  Falco  percgrinus, 
represented  in  the  former  cave  by  four  specimens,  is  wanting  in 
the  latter.  The  owls  are  represented  by  five  specimens  in  the 
former  and  eleven  in  the  latter,  the  grouse  by  thirty-four  in 
the  former  as  against  one  hundred  and  twenty-four  in  the 
latter. 

This  difference  of  faunal  proportions  is  perhaps  most  readily 
explained  by  the  probable  difference  between  the  original  open- 
ings of  the  caves.  Let  it  be  conceded  that,  as  suggested  by  the 
respective  authors,  Potter  Creek  Cave  opened  by  a  relatively 
small  chimney  or  two  on  the  surface  of  the  Pleistocene  hillside 
and  that  Samwel  Cave  opened  by  a  large  chamber,  the  first  part 
of  which  ran  more  nearly  horizontally.  Vultures,  ravens,  and  the 
peregrine  falcon  nest  in  small  cavities  in  rocky  cliffs  out  of  the 
way  of  small  predatory  mammals  like  the  raccoons  and  the 
weasels.  Their  bones  and  those  of  their  prey  would  accumulate 
in  these  pockets  and  eventually  find  their  way  into  deeper  re- 
cesses through  fissures  or  chutes  as  described  by  Sinclair.  The 
owls,  however,  resort  to  large  open-mouthed  caves  to  roost  during 
much  of  the  year,  which  fact  would  account  for  their  greater 
abundance  in  Samwel  Cave.  Raccoons  were  found  in  abundance 
by  Furlong  as  entire  skeletons  on  the  floor  of  Samwel  Cave,  thus 
suggesting  that  these  animals  frequented  the  place  as  a  lair. 
The  ground-dwelling  birds,  their  natural  prey,  thus  come  to 
form  a  large  proportion  of  the  avian  remains  in  these  deposits. 
Procyonid  forms  are  not  listed  by  Sinclair  from  Potter  Creek 


1912 


Miller:  Pacific  Coast  Avian  Palaeontology 


73 


Cave.  They  were  either  absent  from  the  region  or  did  not  fre- 
quent the  vicinity  of  the  cave  mouth.  It  seems  not  improbable 
that  these  small  carnivores  had  a  distinct  relation  to  the  num- 
ber of  gallinaceous  bird  remains  to  become  entombed  in  the 
various  cave  deposits. 

The  following  list  of  mammals  is  recorded  by  Furlong  from 
the  Samwel  Cave: 


FURLONG'S  LIST  or  SPECIES  FROM  SAMWEL  CAVE 


Ursus  americanus  Pallas. 

Ursus,  n.  sp. 

Ursus,   sp. 

Vulpes,   sp. 

Uroeyon  townsendi  Merriam,  C.  H. 

Procyon,  near  lotor  Linn. 

Putorius  arizonensis  Mearns. 

Mephitis  occidentalis  Baird. 

Mustela,  sp. 

Felis,  near  hippolestes  Merriam,  0. 

H. 
Aplodontia,  near  major  Merriam, 

C.  H. 

Aplodontia  rufa  Eafinesque. 
Erethizon  epixanthus  Brandt. 
Arctomys,  sp. 
Lepus  auduboni  Baird. 


Lepus,  sp. 

Thoraorays  monticola  Allen. 

Thomomys,  sp. 

Microtus,  sp. 

Neotoma  fuscipes,  Baird. 

Neotoma,  sp. 

Citellus  douglasi  Richardson. 

Sciurus,  sp. 

Euceratheriura    collinum    Sinclair 

and  Furlong. 

Preptoceras  sinclairi  Furlong. 
Haplocerus,    sp. 
Odocoileus,  sp.  a. 
Odocoileus,  sp.  &. 
Equus    occidentalis   Leidy. 
Elephas,  sp. 
Megalonyx,  sp. 


SPECIES  OF  BIRDS  FROM  SAMWEL  CAVE. 


Indeterminate  anserine  a. 

Indeterminate  anserine  b. 

Indeterminate  anserine  c. 

Oreortyx  picta   (Douglas). 

Indeterminate  odontophorid. 
*Gymnogyps  amplus  Miller. 

Cathartes  aura  (Linnaeus). 
*Catharista  shastensis  Miller. 

Accipiter  velox   (Wilson). 

Buteo  swainsoni  Bonaparte? 


Falco  sparverius  Linnaeus. 

Asio  wilsonianus   (Lesson). 

Bubo  virginianus   (Gmelin). 
*Bubo  sinclairi  Miller. 

Glaucidium  gnoma  Wagler. 
*Micropallas    whitneyi    (J.    G. 
Cooper) . 

Colaptes  cafer    (Gmelin). 

Cyanocitta  stelleri  (Gmelin). 


*  Species  of  birds  marked  with  the  asterisk  (*)  are  extinct  or  else 
foreign  to  the  locality. 

Hawver  Cave. — Hawver  Cave  is  now  located  in  the  same 
faunal  zone  as  the  caves  previously  discussed  and  at  about  the 
same  elevation,  though  some  two  degrees  to  the  southward.  The 


74  University  of  California  Publications  in  Geology     [VoL-  7 

formation  of  the  cave  is  essentially  the  same  except  that  the 
work  of  solution  is  still  probably  going  on  to  some  extent.  The 
method  of  entombment  of  the  organic  remains  appeared  to  Fur- 
long to  be  the  same  as  that  acting  in  the  case  of  Potter  Creek 
Cave,  i.e.,  the  washing  in  of  surface  material  by  the  action  of 
streamlets. 

The  presence  of  Megalonyx  and  Equus  indicate  the  Pleisto- 
cene age  of  the  bone-bearing  deposits  in  the  fissure.  There  ap- 
pear no  remains  of  the  large  ungulates  Euceratherium  and 
Preptoceras  to  correspond  with  the  deposits  of  the  Shasta  caves, 
but  this  condition  may  be  more  apparent  than  real,  since  but 
a  limited  amount  of  work  was  done  in  the  cave  before  the  level 
of  the  water  in  some  of  the  passages  rose  to  a  point  so  high  that 
access  to  the  main  bone-bearing  chambers  was  prevented. 

But  twelve  species  of  birds  are  represented  in  the  collections 
from  this  cave.  Four  of  these  are  no  longer  represented  in  the 
region.  The  fact  that  the  cave  is  still  open  and  that  changes  due 
to  the  action  of  water  are  still  going  on  lends  a  feeling  of  uncer- 
tainty a's  to  the  exact  age  of  any  specimen.  The  association  in 
loose  material  of  remains  which  are  unquestionably  Pleistocene 
in  origin  with  others  representing  still  existing  species  is  no 
guaranty  of  the  age  of  the  latter.  There  is  continually  going 
on  a  measure  of  differential  motion  in  some  of  the  debris  ac- 
cumulated, which  would  possibly  mingle  fragments  deposited 
at  quite  different  times.  Solution,  shifting  and  re-cementing 
may  have  recurred  several  times  although  the  excellent  state  of 
preservation  of  most  of  the  bones  would  militate  against  the  idea 
that  a  great  deal  of  such  movement  had  taken  place. 

The  few  mammals  thus  far  identified  from  Hawver  Cave  are 
listed  as  follows : 

Equus  occidentalis  (?)  Leicly.  Megalonyx,  sp. 

Aplodontia,  sp.  Felis  hippolestes  Merriam,  C.  H. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  75 

LIST  OF  BIRDS  FROM  HAWVER  CAVE. 

*Nettion    carolinense    (Gmelin).  '*Geranoaetus  melanoleucus  Auct.f 

*Oreortyx  picta    (Douglas).  *Colaptes  cafer  (Gmelin). 

*Lophortyx  calif ornica  (Shaw).  *Cyanocitta  stelleri   (Gmelin). 

*Meleagris,  sp.  *Corvus  corax  Linnaeus. 

*Cathartes  aura    (Linnaeus).  *Eup'hagus  cyanocephalus   (Wag- 
*Catharista  shastensis  Miller.  ler). 

*Archibuteo   ferrugineus    (Lichten- 
stein). 

*  An  asterisk  indicates  that  the  species  is  extinct  or  no  longer  found 
in  this  region. 

Rancho  La  Brea. — The  Rancho  La  Brea  beds  constitute  one 
of  the  most  unique  and  at  the  same  time  one  of  the  richest  of 
Pleistocene  deposits  in  the  west;  unique  because  in  the  entomb- 
ment of  remains  the  factor  of  chance  has  been  reduced  to  a 
minimum  by  the  presence  of  an  attractively  baited  and  auto- 
matic trap ;  rich  because  the  trap  was  insatiable  in  its  demands, 
because  the  material  was  promptly  immersed  and  preserved  in 
semi-fluid  asphalt,  and  because  of  the  fact  that  the  trap  was 
almost  continually  operative,  it  would  seem,  for  a  considerable 
period  of  time. 

According  to  Merriam,11  who  bases  his  conclusions  on  per- 
sonal observation  and  upon  the  opinions  of  Arnold,  Orcutt,  and 
other  geologists,  crude  asphaltic  oil  from  the  underlying  Fer- 
nando shales,  here  gently  upfolded,  has  been  forced  to  the  sur- 
face through  cracks  or  chimneys  in  these  folded  strata  to  ac- 
cumulate upon  the  surface  as  more  or  less  extensive  oil  pools. 
This  heavy  oil,  under  the  influence  of  sun  and  wind,  underwent 
a  process  of  natural  distillation,  becoming  more  and  more  viscid 
until  in  the  larger  accumulations  it  was  sufficiently  tenacious 
to  entrap  and  hold  the  largest  mammals  of  the  region,  Elephas, 
Mastodon,  and  Paramylodon.  As  pointed  out  by  the  same 
author,  additions  to  these  lenses  of  asphalt  took  place  at  the 
center  as  fresh  oil  rose  through  the  chimneys  from  below;  at 
the  same  time  dust  and  sand  drifted  over  and  obscured  the 
firmer  asphalt  of  the  margins.  These  two  factors  combined  to 
bring  about  a  most  deceptive  condition  in  the  mass  by  leaving 
the  periphery  fairly  firm  and  yet  permitting  a  gradually  increas- 


11  Merriam,  J.  C.,  Mem.  Univ.  Calif.,  vol.  1,  No.  2,  pp.  199-213,  1911. 


76  University  of  California  Publications  in  Geology     [VOL.  7 

ing  degree  of  plasticity  toward  the  center  without  a  positive  de- 
marcation of  the  danger  zone.  Upon  this  treacherous  surface 
a  mammal  would  be  unaware  of  danger  until  the  dust-covered 
surface  yielded  under  his  weight.  His  sudden  start  or  his  leap 
for  safety  would  make  all  the  more  complete  his  entanglement. 

While  these  exposed  traps  must  have  been  in  many  cases  pas- 
sive, concealed  in  an  open  or  perhaps  but  slightly  wooded 
locality  where  animals  would  blunder  into  them,  they  must  often 
also  have  been  actively  attractive  to  animals  through  the  two 
important  factors  of  water  and  food.  During  a  considerable 
period  of  time  spent  in  working  these  fascinating  deposits,  the 
author  has  had  frequent  recourse  to  the  water  accumulated  in 
depressions  of  the  asphalt.  This  water  has  proven  quite  accept- 
able for  drinking  and  for  bathing.  As  algae  accumulate,  frogs, 
toads,  dragonflies,  mosquitoes,  and  other  insect  forms  invade 
it;  rushes  and  marsh-grass  border  the  pools,  their  roots  actually 
in  contact  with  asphalt  of  the  highest  degree  of  tenacity.  In 
a  number  of  cases  the  asphalt  accumulations  represent  depres- 
sions in  the  general  surface  of  the  country  where  not  only  the 
direct  rainfall  would  be  temporarily  held  empounded  but  more 
lasting  pools  representing  surface  drainage  or  even  seepage 
would  accumulate.  The  presence  of  bedded  leaf-masses  and  of 
water-worn  fragments  of  wood  intermingled  with  the  animal 
remains  would  support  the  view  that  there  were  at  times  ponds 
of  a  more  or  less  permanent  nature.  The  animals  of  poorly 
watered  regions  in  the  southwest  are  perforce  far  from  fas- 
tidious in  the  matter  of  drinking  water;  hence  the  herbivorous 
mammal  must  certainly  have  found  the  vicinity  of  these  water 
pools  one  offering  very  positive  attraction  as  to  water  and 
perhaps  grass  as  well. 

The  entanglement  of  one  ungulate  would  suffice  to  attract 
a  multitude  of  carnivores.  The  creature  probably  acted  not 
infrequently  as  live  bait  for  a  considerable  time,  so  that  its 
struggles  and  outcries  served  to  whet  the  appetites  and  overcome 
the  instincts  of  caution  in  the  hungry  carnivore.  It  appears 
from  Merriam's  studies  that  young  animals  or  else  old  or  dis- 
eased individuals  have  very  frequently  been  thus  tempted, 
though  there  appear  animals  of  all  ages. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  77 

The  prevailing  conditions  also  led  to  a  greatly  distorted 
relation  between  predaceous  and  non-predaceous  species  in  point 
of  numbers.  While  removing  a  single  femur  of  Paramylodon 
there  were  found  touching  it  three  complete  skulls  of  Canis 
indianensis,  and  even  this  proportion  of  three  to  one  is  much 
too  small  to  represent  the  facts  truthfully.  In  a  collection  of 
bird  remains  made  by  the  writer  the  number  of  specimens  of 
Aquila  exceeds  the  number  representing  all  the  non-raptorial 
species  combined,  while  fifty-six  per  cent  of  the  species  recorded 
are  predatory. 

The  cessation  of  struggling  on  the  part  of  the  entrapped 
animal  did  not  end  its  services  as  trap  bait.  Some  forms  which 
normally  seek  an  active  prey,  e.g.,  Canis  and  Aquila,  may  on 
occasion  resort  to  carrion.  A  decrepit  wolf  or  a  hungry  eagle 
may  not  infreqently  thus  supply  the  demands  of  necessity.  The 
odors  emanating  from  these  pits  where  freshly  excavated  are, 
to  human  nostrils,  strongly  suggestive  of  carrion.  Gases  exhaled 
by  animal  bodies  submerged  in  the  plastic  mass  would  accen- 
tuate this  olfactory  effect  to  such  a  degree  as  probably  to  attract 
carrion  feeders.  Was  this  influence  also  felt  by  birds?  Dar- 
win's well-known  experiments  on  Andean  condors  kept  in  cap- 
tivity have  long  been  accepted  as  proving  that  the  vultures  do 
not  employ  the  olfactory  sense  in  the  perception  of  food.  How- 
ever, the  experiences  of  later  naturalists  with  Cathartes,  which 
is  often  caught  in  wolf-traps  with  concealed  bait,  leads  us  to 
emphasize  the  fact  that  Darwin  was  experimenting  with  birds  in 
captivity  which  had  been  fed  perhaps  from  early  youth  in  more 
or  less  regular  fashion.  We  must  at  least  concede  it  possible 
that  the  abundant  vulture  remains  in  the  asphalt  are  the  result 
in  part  of  this  factor  of  odor  in  attracting  them  to  the  locality. 


78 


University  of  California  Publications  in  Geology     [VOL.  7 


PARTIAL  LIST  OF  MAMMALS  FROM  EANCHO  LA  BREA. 


*Canis  indianensis  Leidy. 

*Canis  orcutti  Merriam,  J.  C. 

*Canis  andersoni  Merriam,  J.  C. 

*Canis    occidentalis    furlongi    Mer- 
riam, J.  C. 

*Lynx    occidentalis    fischeri    Mer- 
riam, J.  C. 

*Felis  atrox  bebbi  Merriam,  J.  C. 

*Smilodon  californicus  Bovard. 
Mephitis,    sp. 


Putorius,  sp. 

*Arctotherium    californicum   Mer- 
riam, J.  C. 
*Elephas,  sp. 
*Mastodon,  sp. 
*Equus,  sp. 
*Bison  antiquus  Leidy. 
*Capromeryx  minor  Taylor. 
*Camelops   (?),  sp. 
*Paramylodqn,   sp. 


SPECIES  OF  BIRDS  KNOWN  FROM  RANCHO  LA  BREA. 


Haliaetus     leucocephalus     (Lin- 
naeus) . 

*Morphnus  woodwardi  Miller. 
*Geranoaetus  grinnelli  Miller. 
*Geranoaetus  fragilis  Miller. 

Falco  p'eregrinus   Tunstall. 

Falco,  sp. 

Falco  sparverius  Linnaeus. 
*Polyborus  tharus  Auct. 

Alueo  pratincola  (Bonaparte). 

Asio  flammeus  (Pontoppidan). 

Otus  asio    (Linnaeus). 

Bubo  virginianus   (Gmelin). 

Speotyto   cunicularia    hypogaea 

(Bonaparte). 
*Neomorpha,   ?  sp. 

Colaptes  cafer    (Gmelin). 

Otocoris  alpestris    (Linnaeus). 

Corvus   corax   Linnaeus. 

Corvus  brachyrhynchos  Brehm. 
*  Corvus,  sp. 

Xanthocephalus    xanthocep'halus 
(Bonaparte). 

Agelaius  gubernator   (Wagler). 

Sturnella   neglecta   Audubon. 

Pipilo,  sp. 

Lanius  ludovicianus  Linnaeus. 

*  Species  marked  with  an  asterisk  (*)  are  extinct  or  foreign  to  the 
locality. 

Fossil  Lake. — The  horizon  designated  by  Cope  as  Silver  Lake 
and  classed  collectively  with  several  other m  horizons  as  the  Equus 
Beds,  was  thought  for  many  years  to  be  of  Pliocene  age  and 
as  such  was  considered  by  Cope  and  by  Shufeldt  in  their  studies 


Chaulelasmus  streperus   (Lin- 
naeus). 

Anser  albifrons   (Scopoli)    ? 

Branta  canadensis  (Linnaeus). 
*Cieonia  maltha  Miller. 

Jabiru  mycteria  (Lichtenstein). 

Mycteria  americana  Linnaeus. 

Ardea  herodias  Linnaeus. 
*Grus  minor  Miller. 

Grus  canadensis  (Linnaeus). 

Lophortyx  sp. 
*Meleagris   ? 
*Pavo   californicus   Miller. 

Gymnogyps  calif ornianus  (Shaw). 
*Sarcorhamphus  clarki  Miller. 
*Pleistogyps  rex  Miller. 
*Cathartornis  gracilis  Miller. 

Cathartes  aura    (Linnaeus). 
*Catharista  occidentalis  Miller. 
*Teratornis  merriami  Miller. 

Elanus  leucurus   (Vieillot). 

Circus  hudsonius  (Linnaeus). 
*Circus,   sp. 

Buteo,  sp. 

Buteo  borealis    (Gmelin). 

Aquila  chrysaetos  (Linnaeus). 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology    •  79 

of  the  birds  from  that  region.  Our  knowledge  of  the  various 
western  horizons  has,  however,  been  extended  by  later  investiga- 
tors in  stratigraphy  and  in  the  correlation  of  faunas,  with  the 
result  that  these  beds  are  now  proven  unquestionably  to  be  of 
Pleistocene  age.  Such  change  of  interpretation  alters  materially 
the  significance  of  discoveries  announced  by  Cope  and  by  Shu- 
feldt  in  that  it  reduces  appreciably  the  extent  to  which  several 
existing  genera  are  known  to  run  back  in  time. 

The  various  descriptions  of  this,  region  are  summarized  in  a 
concise  and  very  lucid  paragraph  or  two  by  Osborn12  from  which 
the  following  may  well  be  quoted : 

"One  hundred  and  fifty  miles  northwest  of  the  old  Lahontan  shore 
lines  in  the  heart  of  the  Oregon  Desert  of  the  great  basin,  and  twenty 
miles  northeast  of  Silver  Lake,  there  is  a  slight  depression  in  the  desert 
perhaps  twenty  acres  in  extent  marked  Christmas  Lake  on  the  maps,  to 
which  Cope  gave  the  name  'Fossil  Lake.'  This  ' Silver/  'Christmas,'  or 
'Fossil'  lake  region  was  successively  explored  by  Condon,  Cope,  Sternberg 
(who  made  the  chief  collections),  and  Eussel  (1882).  .  .  .  Though  actually 
twenty  miles  distant  from  Silver  Lake,  the  rich  fauna  of  mammals  and 
birds  found  has  been  described  by  Copei3  and  Shufeldt,  and  referred  to  by 
Gilbert,  as  the  fauna  of  the  Silver  Lake  Equus  beds.  .  .  . 

"Proof  that  the  country  was  partly  fluviatile  and  partly  wooded  is 
afforded  by  the  presence  of  the  muskrat  (Fiber},  the  otter  (Lutra),  the 
beaver  (  Castor  fiber),  and  the  giant  beaver  (Castoroides) . 

"  ....  The  bird  life  was  very  abundant  and  not  very  dissimilar  from 
what  we  might  observe  at  any  of  the  alkaline  lakes  of  the  West,  resorted 
to  at  the  present  day  by  wild  fowl  during  their  migrations.  Great  flocks 
of  swans  (Cygnus  paloregonus) ,  geese  (Anser  condoni),  and  ducks  were 
there;  a  cormorant  (PTialacrocorax)  was  among  the  rarities;  among  the 
species  of  grebe  (Podiceps  occidentalis)  is  one  still  inhabiting  this  region. 
There  were  also  coots  (Fulica  minor)  and  herons  (Ardea  paloccidentalis) . 
Other  forms  of  birds  include  two  species  of  grouse,  crows,  and  eagles.  The 
strangest  figure  upon  the  scenes  among  the  birds  was  a  true  flamingo 
(Phoenicopterus  copei}.  The  northernmost  distribution  of  flamingoes  at 
the  present  is  southern  Florida  and  the  Bahama  Islands  (lat.  27°  N). 
Shufeldt  concludes  that  the  climate  might  well  be  compared  with  that  of 
Florida  or  the  lower  part  of  Louisiana,  that  the  vegetation  was  fully  as 
luxuriant  as  it  now  is  in  those  parts,  and  that  the  palms  were  abundantly 
represented.  This  conclusion  as  to  a  Floridan  climate  and  the  existence 
of  palms  is,  however,  very  questionable.  Brown14  observes  that  the  South 
American  flamingoes  (Phoenicopterus  chilensis}  migrate  as  far  south  as 


12  Osborn,  H.  F.,  The  Age  of  Mammals,  p.  458. 

is  Cope,  E.  D.,  The  Silver  Lake  of  Oregon  and  its  Region,  Am.  Nat.,  vol. 
23,  pp.  970-982,  1889. 

14  Mr.  Barnum  Brown  in  a  note  to  the  author  [Osborn]. 


80 


University  of  California  Publications  in  Geology     [VOL.  7 


the  lakes  in  central  eastern  Tierra  del  Fuego,  lat.  53°  S,  where  they  are 
said  to  breed,  and  certainly  spend  a  part  of  the  season.  This  region  cor- 
responds in  temperature  to  the  climate  of  central  Alberta,  Canada,  400 
miles  north  of  Silver  Lake.  Thus  it  appears  that  the  presence  of  Phoenicop- 
terus  copei  at  Silver  Lake  has  very  little  weight  in  the  determination  of 
climate.  It  is  more  probable  that  the  northern  lakes  of  that  period  con- 
tained mollusks  on  which  the  flamingoes  fed. ' ' 

Aside  from  an  extinct  genus  of  grouse,  Phoenicopterus  is  the 
only  genus  recorded  fossil  that  might  not  reasonably  be  expected 
to  occur  in  the  region  at  the  present  time. 

Shufeldt's  original  paper15  gives  a  detailed  description  of 
most  of  the  species  of  birds  found  in  the  Fossil  Lake  beds  and 
a  synoptical  list  of  the  known  species  was  published  in  a  paper 
by  the  writer16  as  follows: 


^chmophorus  occidentalis  (Lawrence) 


Pygopodes : 


Lougipennes : 


Steganop'odes : 
Anseres : 


yEchmophorus  occidentalis  (Lawrence). 

Colymbus  holboelli  (Eeinhardt). 

Colymbus  auritus   Linneus. 

Colymbus  nigricollis  calif ornicus  (Heermann), 

Podilymbus  podiceps  (Linneus). 

Larus  argentatus  Pontoppidan. 

Larus  robustus  Shufeldt. 

Larus  californicus  Lawrence. 

Larus  oregonus  Shufeldt. 

Larus  Philadelphia   (Ord). 

Xema  sabini   (J.  Sabine). 

Sterna  elegans  Gambel. 

Sterna  forsteri  Nuttall. 

Hydrochelidon  nigra  surinamensis   (Gmelin). 

Phalacrocorax  macropus  (Cope). 

Pelecanus  erythrorhynchos  Gmelin. 

Lophodytes  cucullatus   (Linnaeus). 

Anas  platyrhynchos  Linnaeus. 

Mareca  americana   (Gmelin). 

Nettion  carolinense    (Gmelin). 

Querquedula  discors  (Linnaeus). 

Querquedula  cyanoptera   (Vieillot). 

Spatula  clypeata  (Linnaeus). 

Dafila  acuta  (Linnaeus). 

Aix  sponsa  (Linnaeus). 


is  Shufeldt,  E.  W.,  Journ.  Acad.  Nat.  Sci.  Phila.,  ser.  2,  no.  9,  pp.  389- 
45,  1892. 

is  Miller,  L.  H.,  Univ.  Calif.  Publ.,  Bull.  Dept.  Geol.,  vol.  6,  pp.  79-87, 
1911. 


1912] 


Miller:  Pacific  Coast  Avian  Palaeontology 


81 


Marila  valisineria  (Wilson). 

Clangula  islandica   (Gmelin). 

Harelda  hyemalis  (Linnaeus). 

Anser  condoni  Shufeldt. 

Anser  albifrons  gambeli  Hartlaub. 

Branta  hypsibata  Cope. 

Branta  canadensis  (Linnaeus). 

Branta  propinqua   Shufeldt. 

Chen  hyperboreus   (Pallas). 

Olor  paloregonus   (Cope). 

Odontoglossae :         Phoenicopterus  copei  Shufeldt. 
Herodiones:  Ardea  paloccidentalis  Shufeldt. 

Paludicolae:  Fulica  americana  Gmelin. 

Fulica  minor  Shufeldt. 

Limicolae:  Lobipes  lobatus  (Linnaeus). 

Gallinae:  Tympanuchus  pallidicinctus   (Ridgway). 

Pedioecetes  phasianellus  columbianus  (Ord). 

Pedioecetes  lucasi  Shufeldt. 

Pedioecetes  nanus   Shufeldt. 

Palaeotetrix   gilli  Shufeldt. 
Accipitres:  Aquila  pliogryps  Shufeldt. 

Aquila  sodalis  Shufeldt. 

Striges:  Bubo  virginianus   (Gmelin). 

Passeres:  Euphagus  affinis  Shufeldt. 

Corvus  annectens  Shufeldt. 

ADDITIONAL  SPECIES  OP  BIRDS  IN  THE  CALIFORNIA  COLLECTIONS 

Pygopodes:  ^chmophorus  lucasi  Miller. 

Anseres:  Erismatura  jamaicensis    (Gmelin). 

Accipitres:  Circus  hudsonius  (Linnaeus).  ~~_ 


PARTIAL  LIST  OF  MAMMALS  FROM  FOSSIL  LAKE.I? 


Ursus,  sp. 
Felis,  sp. 

Canis  latrans  Say. 
Canis,  cf.  occidentalis  Richardson. 
ftVulpes,  cf.  pennsylvanicus  Bodd. 
Lutra  canadensis  Schreber. 
Fiber  zibethicus  Linnaeus. 
Arvicola,   sp. 
Thomomys,    sp. 
Ueomys,  sp. 
Castor,  sp. 
Castoroides,  sp. 


Lepus,  sp. 

Mylodon  sodalis  Cope. 
Equus  pacificus  Leidy. 
Equus,  n.  sp. 
Elephas,  sp. 

Platygonus,  cf.  vetus  Leidy. 
Platygonus,  sp. 
Eschatius  conidens  Cope. 
Camelops  kansanus   Leidy. 
Camelops  vitakerianus  Cope. 
Camelops,  sp. 
Antilocapra,  sp. 


17  Sinclair,  W.  J.,  Univ.  Calif.  Publ.  Am.  Arch.  Ethn.,  vol.  2,  p.  1,  1904. 


82  University  of  California  Publications  in  Geology    [VoL-  7 

Rodeo  Pleistocene. — Almost  nothing  has  been  recorded  con- 
cerning this  formation.  The  region  has  been  repeatedly  visited 
by  parties  from  the  University  of  California  and  the  Pleistocene 
age  of  the  beds  definitely  established. 

The  single  specimen  of  bird  remains  from  the  locality  was 
picked  up  at  the  base  of  the  exposure  by  Professor  J.  C.  Mer- 
riam  with  parts  of  the  matrix  of  the  Pleistocene  beds  still  adher- 
ing to  it.  The  bone  is  a  perfect  tarsometarsus  of  average  size. 

SINGLE  SPECIES  FROM  EODEO  PLEISTOCENE. 
2Echmophorus  occidentalis   (Lawrence). 

PRESENT  PHYSIOGRAPHIC   AND   GEOGRAPHIC   RELATIONS   OF   THE 

WEST  AMERICAN  REGIONS  IN  WHICH  FOSSIL  AVIAN 

REMAINS  ARE   KNOWN 

The  nine  localities  referred  to  above  have  yielded  several 
thousand  specimens  in  all.  Only  five  of  these  specimens,  repre- 
senting three  species,  are  from  deposits  older  than  the  Pleisto- 
cene ;  hence  we  may  consider  our  knowledge  as  practically  limited 
to  that  age.  Since  also  the  systematic  groups  larger  than  the 
species  display  in  the  case  of  birds  such  remarkable  longevity, 
time  relations  between  the  several  Pleistocene  horizons  become 
of  minor  importance  except  as  we  learn  of  variations  in  climate 
during  that  period. 

There  is  on  the  other  hand  an  advantage  to  be  derived  from 
the  approximate  contemporaneity  of  the  deposits.  The  entomb- 
ment of  many  specimens  at  about  the  same  time  under  a  variety 
of  conditions  and  in  a  number  of  different  localities  gives  us 
an  unusually  accurate  conception  of  the  avifauna  of  that  time. 
The  Fossil  Lake  deposits  yield  mainly  those  species  to  be  found 
about  open,  shallow  lakes;  the  caverns  are  so  located  as  to  h 
entombed  those  species  which  inhabit  lower  mountainous  coun- 
try ;  the  Rodeo  Pleistocene  consists  of  seashore  accumulation ;  the 
Rancho  La  Brea  beds  a.re  the  result  of  a  peculiarly  diverse  com- 
bination of  circumstances  which  led  to  the  trapping  of  open- 
plains  birds  with  a  preponderance  of  raptorial  species. 

The  asphalt  beds  lie  in  latitude  34°  N,  on  the  coastal  side  of 
the  Santa  Monica  Mountains  within  a  few  miles  of  the  sea  and 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  83 

less  than  two  hundred  feet  above  its  level.  The -locality  is  today 
a  typical  open  valley  country,  protected  on  the  north  by  the 
east-and-west  Santa  Monica  Range,  yet  tempered  by  the  cool 
and  moisture-laden  breeze  from  the  sea.  Faunally,  the  locality 
lies  in  the  Upper  Sonoran  zone  of  the  San  Diego  region. 

The  Shasta  caves  occupy  a  position  further  inland  and  seven 
degrees  to  the  northward  of  Rancho  La  Brea.  Their  elevations 
vary  between  1300  and  1500  feet  above  sea-level.  The  isothermic 
zone  represented  is  slightly  above  that  of  Rancho  La  Brea,  it 
being  Upper  Sonoran  and  lower  Transition.  The  isohumic  area 
is  that  of  the  Sacramento-San  Joaquin,  which  is  an  area  of 
slightly  greater  precipitation  than  is  the  San  Diegan. 

The  two  localities  are  at  present  distinguishable  in  their  avi- 
fauna by  the  presence  or  the  absence  of  several  species  which 
are  of  interest  in  the  light  of  palaeontological  records.  .  The 
entire  group  of  grouse,  represented  in  the  Shasta  region  by 
Dendragapus,  is  wanting  at  Rancho  La  Brea.  Oreortyx  and 
Cyanocitta,  present  in  the  cave  region,  are  wanting  in  the  im- 
mediate vicinity  of  the  asphalt  beds.  Geococcyx,  present  in  the 
latter  locality,  is  wanting  in  the  former. 

These,  however,  are  birds  of  slight  volant  power.  The  species 
of  less  restricted  activity,  such  as  the  Raptores  and  the  water- 
birds,  are  common  to  the  two  localities  at  present. 

The  Fossil  Lake  region  of  Oregon  lies  in  latitude  43°  N,  full 
nine  degrees  north  of  Rancho  La  Brea,  and  is  on  the  eastern 
side  of  the  Cascade  Range.  This  separation  from  the  coastal 
slope  would  influence  the  smaller  species  of  birds  more  than  the 
larger.  Winter  temperatures  would  be  more  severe,  with  sum- 
mer temperatures  fully  equal  to  those  of  southern  California. 
The  rainfall  at  the  present  time  is  such  as  to  give  the  region 
the  name  of  ''Oregon  Desert." 

There  appears,  then,  as  distinguishing  the  five  more  import- 
ant localities  today,  a  difference  of  nine  degrees  of  latitude,  a 
range  of  elevation  from  100  to  1500  feet  above  the  sea,  and  a 
faunal  difference  limited  to  the  Upper  Sonoran  and  lower 
Transition  zones.  There  is  no  evidence  of  marked  change  in 
elevation  since  Pleistocene  times;  hence  it  seems  probable  that 
a  somewhat  similar  relationship  between  the  localities  prevailed 


84  University  of  California  Publications  in  Geology    [VOL.  7 

during  the  Pleistocene  period  and  that  the  specimens  obtained 
from  the  various  horizons  represent  in  the  aggregate,  with  a 
considerable  degree  of  accuracy,  the  avifauna  of  the  Pacific 
coast  at  that  time. 

RELATION  OF  PLEISTOCENE  FAUNAS  TO  THOSE  OF  THE  PRESENT 

DAY 

A  partial  list  of  the  Recent  birds  of  the  Transition  zone  in 
the  Shasta  region  is  given  in  the  report  of  a  biological  survey 
of  the  region  by  C.  H.  Merriam.18  The  list  is  appended  here 
and  the  more  striking  differences  displayed  by  the  other  locali- 
ties are  noted.  This  comparison  may  prove  of  interest  in  con- 
sidering the  fossil  avifauna. 


EECENT  AVIFAUNA  OF  THE  SHASTA  REGION 
(Partial  list  from  Upper  Sonoran  and  Transition  zones) 


Oreortyx  picta    (Douglas). 
Lophortyx  calif ornica    (Shaw). 
Dendragapus   obscurus    (Say). 
Zenaidura  macroura   (Linnaeus). 
Cathartes  aura    (Linnaeus). 
Circus  hudsonius   (Linnaeus). 
Buteo  borealis    (Gmelin). 
Aquila  chrysaetos  (Linnaeus). 
Falco   mexicanus   Schlegel. 
Falco  sparverius  Linnaeus. 
Bubo   virginianus    (Gmelin). 


Speotyto  cunicularia    (Molina). 
Glaucidium  gnoma  Wagler. 
Colaptes  cafer    (Gmelin). 
Aphelocoma   californica    (Vigors). 
Cyanocitta  stelleri   (Gmelin). 
Sturnella  neglecta  Audubon. 
Euphagus  cyanocephalus  (Wagler). 
Lanius  ludovicianus  Linnaeus. 
Planesticus     migratorius     (Lin- 
naeus). 


To  this  list  may  be  added  the  following  species  which  possibly 
occur  in  the  locality,  though  not  recorded  by  the  collectors  of 
the  survey  party: 


Accipiter  velox    (Wilson). 

Accipiter  cooperi    (Bonaparte). 

Astur  atricapillus    (Wilson). 

Buteo  swainsoni  Bonaparte. 

Archibuteo  ferrugineus   (Lichten- 
stein). 

Haliaetus    leucocephalus     (Lin- 
naeus). 

Gymnogyps   calif ornianus    (Shaw). 


Falco  peregrinus  Tunstall. 
Aluco   pratincola    (Bonaparte). 
Asio   wilsonianus    (Lesson). 
Otus  asio   (Linnaeus)    . 
Geococcyx   calif  ornianus    (Lesson). 
Corvus  corax  Linnaeus. 
Corvus  brachyrhynchos  Brehm. 
Cosmopolitan  water  birds 


is  Merriam,  C.  H.,  Eesults  of  a  Biological  Survey  of  Mt.  Shasta,  Cali- 
fornia, N.  Am.  Fauna,  No.  16,  1899. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  85 

SOME  RECENT  BIRDS  NOTED  IN  THE  SILVER  LAKE  REGION.™ 

Geese,  Swans,  Pelicans,  Cormorants  Oreoscoptes   montanus    (Townsend, 
^chmorphorus   occidentalis    (Law-  J.  K.) 

rence).  Asyndesmus  lewisi  Riley. 

Myadestes  townsendi  (Audubon).  Eecurvirostra  americana  Gmelin. 
Ixoreus  naevius    (Gmelin).  Himantopus    mexieanus     (Miiller). 


If,  as  is  suggested  by  the  configuration  of  the  country,  the 
former  elevation  of  the  caves  was  slightly  less  than  at  present 
and  the  country  less  broken,  conditions  were  then  more  favor- 
able than  at  present  for  such  species  as  Geococcyx  californianus 
and  Archibuteo  ferrugineus.  The  probability  that  slow-moving 
streams  and  small  lakelets  served  to  attract  waders,  anserines, 
and  Haliaetus  would  be  greater  in  such  a  condition  of  the  coun- 
try. 

In  the  vicinity  of  Fossil  Lake,  Oregon,  the  present  avifauna 
would  show  probably  several  points  of  divergence  from  the  cave 
region  and  from  Rancho  La  Brea.  Oreortyx,  Cyanocitta,  Aphe- 
locoma,  and  Geococcyx  would  probably  be  lacking,  while  one 
would  doubtless  meet  with  Pedioecetes,  Centrocercus  and  Cyano- 
ceplialus. 

At  Rancho  La  Brea,  Elanus  and  Geococcyx  would  prove  more 
abundant,  Agelaius,  Xanthocephalus,  and  Otocoris  would  be 
plentiful,  while  Dendragapus,  Oreortyx,  and  Cyanocitta  would 
not  be  likely  to  occur.  Elanus  and  Geococcyx  at  Rancho  La 
Brea,  Dendragapus  in  the  Shasta  region  and  Centrocercus  and 
Pedioecetes  in  the  Fossil  Lake  region  are  the  chief  differences 
dependent  upon  latitude  to  be  noticed  among  the  three  faunas. 
The  other  discrepancies  are  such  as  would  be  due  to  slight  differ- 
erence  in  altitude,  the  proximity  of  water  or  the  topography"  of 
the  region. 

The  long  list  of  smaller  passerines,  piciforms  and  machro- 
cheirs  is  here  purposely  omitted,  since  they,  though  very  im- 
portant in  the  determination  of  faunal  zones,  seem  not  to  have 
been  preserved  in  the  fossil  state  to  any  great  extent. 

Distribution  of  the  Cathartidae. — One  of  the  groups  of  chief 
interest  in  discussing  the  subject  of  distribution  in  the  light 


19  Cope,  E.  D.,  The  Silver  Lake  of  Oregon  and  its  Region,  Am.  Nat.,  vol. 
23,  p.  970,  1839. 


86  University  of  California  Publications  in  Geology    [V°L-  7 

of  palaeontological  study  is  the  raptorial  subdivision  embracing 
the  New  World  vultures.  The  exclusive  possession  by  the 
Americas  of  so  marked  a  group  of  large  and  strong-flying  birds 
as  the  Cathartidae  and  the  total  absence  there  of  any  form  of 
the  true  Vulturidae,  which  occupy  the  same  bionomic  position 
in  the  Old  World,  is  one  of  the  striking  phenomena  in  animal 
distribution.  Aside  from  the  fact  that  the  group  is  so  well 
defined,  there  being  no  Recent  forms  showing  transition  between 
it  and  the  other  raptorine  subdivisions,  we  find  it  not  poor  in 
species  and  it  is  widely  distributed  in  the  western  hemisphere. 

There  are  endemic  to  the  New  World  no  less  than  five  distinct 
cathartine  genera — a  goodly  number  for  a  group,  the  smallest 
member  of  which  approaches  in  size  the  largest  eagles.  All  are 
birds  capable  of  long-sustained  flights  and  they  are  unsurpassed 
in  their  ability  to  meet  the  emergencies  of  changed  elevation 
and  shifting  air  currents  that  would  prove  disturbing  to  less 
perfect  fliers.  This  very  factor  may,  by  insuring  them  against 
being  driven  astray  by  storms,  bring  about  a  distribution  more 
in  accord  with  their  own  needs  or  inclinations. 

As  an  instructive  comparison  in  the  matter  of  distribution 
one  might  consider  the  short-eared  owl  (Asio  flammeus).  This 
bird  is  almost  cosmopolitan,  occurring  unmodified  over  both 
hemispheres  and  even  in  such  isolated  islands  as  the  Hawaiian 
group,  though  no  more  maritime  and  no  more  capable  a  flier 
than  the  cathartid  vultures.  It  might  be  suggested  as  a  dis- 
tinction between  these  two  cases  that  the  vultures  are  non- 
migratory  and  are  confined  to  the  tropics,  and  would,  therefore, 
have  no  tendency  to  wander,  would  not  be  exposed  to  the  danger 
of  scattering  by  storms  and  would  always  be  separated  from  the 
other  continents  by  the  widest  parts  of  the  ocean  basins.  An 
examination  of  the  ranges  and  the  habits  of  the  existing  species 
will,  however,  prove  the  fallacy  of  such  views.  Cathartes  aura 
is  migratory  or  not  as  occasion  demands.  It  is  resident  to  40°  N 
latitude  and  thence  northward  ,it  becomes  migratory,  being 
starved  out  in  winter.  Its  habitual  range  extends  from  55°  N 
latitude  to  Tierra  del  Fuego  and  the  Falkland  Islands  on  the 
south.20 


20  Coues,  E.,  Key  to  N.  Am.  Birds  (ed.  5;  1903),  vol.  2. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  87 

Other  members  of  the  group  range  as  follows:  The  Andean 
condor  (Sarcorhamphus)  occurs  along  the  Cordillera  from 
equatorial  Peru  to  the  extremity  of  Patagonia  and  from  sea- 
level  to  the  highest  summits  of  the  Andes;  Catharista  urubu 
inhabits  the  whole  of  tropical  America,  southward  to  Argentina 
and  northward  as  a  straggler  to  the  Canadian  border ;  the  two 
remaining  genera,  Gyparclms  and  Gymnogyps,  occupy  succes- 
sively more  circumscribed  areas.  Not,  however,  till  the  latter 
was  so  nearly  exterminated  by  human  agency,  was  either  form 
of  restricted  range.  Gymnogyps  is  confined  entirely  to  the 
Nearctic  realm,  Sarcorhampkus  is  entirely  Neogaeic,  but  the  three 
remaining  forms  are  distributed  without  regard  to  realm  and 
all  are  independent  of  the  generally  recognized  life-zones.  That 
a  group  thus  distributed,  many  of  whose  members  are  so  in- 
dependent of  climatic  and  of  minor  geographic  barriers,  should 
be  limited  to  the  western  hemisphere  seems  indeed  strange. 

The  influence  of  a  virile  and  aggressive  species  is  not  infre- 
quently effective  as  a  barrier  to  the  distribution  of  a  less  active 
one  and  it  may  be  urged  that  the  slightly  more  rapacious  vul- 
turines  of  the  Old  World  have  served  as  a  check  upon  any  ten- 
dency of  the  cathartids  to  diffuse  into  Eurasia.  Such  a  view  is 
controverted  by  the  fact  that  the  latter  birds  prove  themselves 
perfectly  able  to  maintain  their  existence  in  competition  with 
the  polyborine  scavengers  which,  in  a  .way,  represent  the  Old 
World  vultures  in  their  habits. 

With  the  geographical  limitations  of  the  group  before  us,  the 
question  of  ancestry  and  the  geological  record  assume  a  very 
important  aspect. 

Concerning  the  antiquity  of  the  group  there  is  unfortunately 
but  little  known.  Previous  to  the  opening  up  of  the  Rancho  La 
Brea  deposits  in  California,  fossil  cathartids  of  unquestionable 
identity  were  unknown  to  North  America.  Cope's  Palaeoborus 
umbrosus^  from  the  Pliocene  of  New  Mexico,  which  he  orig- 
inally placed  in  the  genus  Cathartes,  he  later  transfers  to  the 
genus  Vultur.  The  new  genus  Palaeoborus  was  established  by 
Coues  for  its  reception  since  "  ....  the  description  and  figures 


21  Cope,  E.  D.,  U.  S.  G.  Surv.  W.  of  100th  MericL,  vol.  4,  pt.  2,  p.  287, 
1876. 


88  University  of  California  Publications  in  Geology    [VOL.  7 

clearly  indicate  a  bird  generically  distinct  from  Cathartes  and  the 
improbability  of  the  occurrence  of  a  true  Vultur  in  North 
America  is  extreme. '  '22  With  the  former  point  at  least  there  can 
be  no  possible  disagreement  after  a  consideration  of  Cope 's  figures 
of  Palaeoborus.  Whether  the  form  may  be  considered  cathartine 
at  all  is  open  to. very  serious  question.  Lucas23  considers  it  as 
more  probably  of  polyborine  affinities. 

In  South  America  fossil  cathartids  are  less  rare.  Cathartes 
and  Gyparchus  are  reported  from  the  Pleistocene  caves  of 
Brazil.24  Moreno  and  Mercerat25  describe  two  species  from  the 
Pampean  Pleistocene  and  three  from  the  Pliocene  of  the  Santa 
Cruz.  The  Pleistocene  species,  Cathartes  fossilis  and  Sarco- 
rhamphus  fossilis,  represent  genera  still  existing  in  that  region. 
The  three  species  from  the  Santa  Cruz,  Psilopterus  communis, 
P.  australis  and  P.  intermedius,  belong  to  an  extinct  genus  which 
is  placed  by  the  authors  adjacent  to  Cathartes  and  is  considered 
by  them  to  be  intermediate  or  transitional  between  that  genus 
and  Sarcorhamphus.  The  three  species  of  Psilopterus  are  based 
on  the  most  fragmentary  material.  The  figures  are  such  as  to 
indicate  specimens  in  rather  poor  state  of  preservation  as  to  sur- 
face markings.  Trochleae  are  corroded  away  and  intermuscular 
lines  are  entirely  wanting.  P.  intermedius  is  based  on  a  single 
specimen  consisting  of  two  tarsal  trochleae.  The  other  two 
species  are  based  upon  fragmentary  tarsi  poorly  preserved. 
While  there  may  be  no  question  in  the  minds  of  these  authors 
as  to  the  relationships  of  the  genus  Psilopterus,  there  appears 
nothing  in  the  lithographed  figures  or  in  the  very  meager  descrip- 
tions that  is  at  all  convincing. 

Beyond  the  above  instances,  the  only  record  of  fossil  cath- 
artids previous  to  the  excavations  at  Rancho  La  Brea  is  the 
remarkable  specimen  made  known  by  Gaillard26  from  the  phos- 
phorites of  Quercy,  an  Oligocene  horizon  in  France.  This  species, 


2-2  Coues,  E.,  Key  to  N.  Am.  Birds  (ed.  2;  2884),  p.  822. 

23  Lucas,  F.  A.,  in  Zittel's  Text-Book  of  Palaeontology,  Eng.  trans.,  vol. 
2,  p.  277,  1902. 

24  Winge,  O.,  Fugle  fra  Knoglehaler  i  Brazilien,  Museo  Lundii,  1887. 

25  Palae.  Argentina,  An.  Mus.  La  Plata,  pt.  1,  p.  67,  1891. 

26  Gaillard,  C.,  Ann.  de  1  'Univ.  de  Lyon,  n.  ser.  1,  Sc.  &  Med.,  fasc.  23, 
1908. 


191 2]  Miller:  Pacific  Coast  Avian  Palaeontology  89 

Plesiocarthartes  europeus  Gaillard,  thus  becomes  at  once  the 
most  ancient  cathartid,  and  the  only  instance  known  to  the 
author  of  the  occurrence,  fossil  or  Recent,  of  the  family  outside 
the  American  continents.  The  species,  as  far  as  can  be  learned, 
is  represented  by  a  single  bone,  a  fragmentary  tarsometatarsus 
preserved  in  the  Museum  of  Lyons.  The  specimen  is,  however, 
sufficient  to  establish  beyond  question  the  cathartine  relation- 
ships of  the  species.  Its  author  considers  the  case  to  be  one  of 
an  individual's  having  straggled  from  its  normal  range.  In 
view  of  the  extensive  examination  of  most  of  the  European 
horizons  which  has  failed  thus  far  to  furnish  evidence  of  its 
further  occurrence  there,  the  conclusions  reached  by  Dr.  Gail- 
lard  may  be  considered  as  probably  correct. 

With  the  progress  of  work  at  the  University  of  California 
our  knowledge  of  the  group  under  discussion  is  considerably 
advanced.  In  the  collections  from  Fossil  Lake  the  abundant 
avian  remains  are  almost  entirely  of  aquatic  forms,  although 
there  appear  in  the  University  collections,  as  well  as  in  the  much 
larger  Cope  and  the  Condon  collections,  a  number  of  raptorial 
species.  There  are,  however,  no  specimens  referable  to  the  Cath- 
artidae,  a  rather  conspicuous  absence. 

There  appears  no  reason  deducible  from  the  habits  of  the 
turkey,  vulture  of  today  why,  if  vultures  were  present  during 
the  formation  of  these  beds,  their  remains  should  not  have  been 
preserved  there.  In  fact,  there  is  every  reason  for  considering 
the  vulture  a  more  favorable  subject  for  preservation  in  such 
deposits  than  are  the  other  raptors.  The  turkey  vulture  is  one 
of  the  commonest  of  beach-combers  along  the  shores  of  both  fresh 
and  salt-water  bodies  and  it  comes  habitually  in  great  flocks  to 
spend  the  warmer  parts  of  the  day  wading  in  the  shallower 
waters  or  sitting  about  the  sand  bars  of  quiet  streams.  The 
negative  evidence  very  strongly  suggests  the  absence  of  cath- 
artids  from  the  region  during  the  deposition  of  the  Fossil  Lake 
beds. 

Potter  Creek  and  Samwel  caves  both  furnish  remains  of 
these  vultures,  while  the  Rancho  La  Brea  asphalt  is  especially 
rich  in  raptorial  species,  about  equally  divided  between  the  cath- 
artids  and  the  falconids. 


90  University  of  California  Publications  in  Geology    [VOL.  7 

At  Rancho  La  Brea  there  occur  six  truly  cathartine  species 
as  follows:  Gymnogyps  calif ornianus,  Sarcorhamphus  clarlci, 
Cathartornis  gracilis,  Pleistogyps  rex,  Cathartes  aura,  and  Cath- 
arista  occidentalis.  Besides  these  forms,  the  aberrant  Teratornis 
is  nearer  to  the  Cathartidae  than  to  any  other  family  at  present 
recognized.  In  the  cave  deposits  there  appear  the  two  forms, 
Catliarista  shastensis  and  Gymnogyps  amplus,  belonging  to  ex- 
isting genera. 

The  condors  and  Teratornis  represent  the  extreme  of  spe- 
cialization in  point  of  size,  the  greatest  degree  of  diversity,  and 
possibly  also  the  least  specific  longevity.  Gymnogyps  calif  orni- 
anus alone  of  the  six  larger  forms  has  persisted  unchanged  from 
the  time  of  formation  of  the  asphalt  beds,  where  it  is  the  most 
abundant  of  the  condors,  until  the  present  time,  when  it  seems 
on  the  verge  of  extinction.  Probably  its  associates  of  that  time 
had  passed  the  prime  of  their  specific  existence  while  the  present 
form,  less  specialized  toward  gigantism,  constituted  a  younger 
development  reaching  its  maximum  of  virility  later  than  its 
congeners  but  becoming  decadent  by  the  present  time. 

As  a  result  of  the  excavations  at  Rancho  La  Brea  the  genus 
Catliarista  became  known  to  the  Pleistocene  of  North  America, 
its  first  discovery  in  the  fossil  state.  Its  range  was  at  the  same 
time  extended  from  its  previous  limits — the  tropical  and  lower 
Austral  zones  of  both  continents — to  include  the  Pacific  Coast 
region  of  California,  an  area  at  present  occupied  by  an  Upper 
Sonoran  fauna.  The  fossil  species  C.  occidentalis  is  found  in 
great  abundance  in  the  asphalt.  Its  relative  abundance  as  com- 
pared with  the  other  vultures  there  is  shown  by  a  census  of  an 
unassorted  collection  of  the  bird  remains,  which  gave  the  fol- 
lowing results : 

Gymnogyps  californianus  11  individuals 

Cathartes  aura    20  individuals 

Catliarista  occidentalis 21  individuals 

As  indicated  in  the  note  descriptive  of  Catharista  occidentalis, 
the  difference  between  the  fossil  and  the  Recent  forms  lies  in  the 
greater  body  size  of  the  fossil  form  accompanied  by  a  difference 
in  proportion  of  the  segments  of  the  posterior  limb.  The  tarsus 
Polyborus  there  appear  the  following  fossil  forms  whose  nearest 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  91 

shows  a  greater  degree  of  robustness,  both  absolute  and  relative. 
The  humerus  is  slightly  longer  and  stouter,  but  whether  the  wing 
expanse  is  increased  to  a  degree  commensurate  with  the  in- 
creased body  weight  is  questionable.  We  seem,  then,  to  be  deal- 
ing with  a  vulture  that  was  of  a  heavier  body  and  shorter 
limb  than  the  persistent  Catharista  urubu.  The  difference  be- 
comes more  significant  when  it  is  noted  that  the  character  separ- 
ating the  extinct  from  the  persistent  species  of  Catharista  is 
identical  with  one  of  those  separating  the  more  restricted  Cathar- 
ista urubu  from  the  wider  ranging  Cathartes  aura.  It  should 
also  be  noted  that  the  extinct  form  Catharista  shastensis  from 
the  caves  is  separable  from  the  Rancho  La  Brea  species,  C.  Occi- 
dentalis,  by  a  greater  robustness  of  the  tarsometatarsus  and 
by  a  greater  body  size  as  indicated  by  its  stouter  coracoid.  The 
cave  form,  the  asphalt  form,  and  the  Recent  form  of  Catharista 
thus  fall  with  the  Recent  Cathartes  into  a  series  of  progressively 
lighter-bodied  and  possibly  more  strongly  flying  vultures,  which 
display,  in  the  cases  of  the  last  three  at  least,  a  progressively 
greater  ability  to  cope  with  their  environment. 

That  the  cavern  and  the  asphalt  deposits  are 'not  of  the  same 
age  is  evidenced  by  the  occurrence  therein  of  distinct  but  closely 
related  species  of  cathartids  belonging  to  two  genera,  i.e.  Gym- 
nogyps  and  Catharista.  The  localities  are  separated  by  approx- 
imately seven  degrees  of  latitude  and  a  difference  in  elevation 
of  fourteen  hundred  feet.  Both  lie  at  present  in  approximately 
the  same  faunal  zone.  Species  possessed  of  the  excellent  volant 
powers  shown  by  the  large  vultures  when  present  in  the  con- 
siderable numbers  indicated  by  their  remains  in  the  two  deposits 
would  scarcely  feel  the  restrictions  of  such  slight  barriers  as 
could  have  existed  at  that  time. 

The  existing  species  of  Gymnogyps,  before  its  numbers  were 
depleted  by  the  influence  of  man,  ranged  from  Lower  California 
to  British  Columbia  and  from  sea-level  to  the  summits  of  the 
Coast  Range,  while  the  existing  Cathartes  is  almost  ubiquitous. 
Furthermore  our  knowledge  of  the  Recent  vultures  as  a  group 
would  lead  us  to  discard  as  incongruous  the  conception  of  a 
vulture  so  strictly  boreal  as  to  come  southward  in  considerable 
numbers  as  far  as  the  Shasta  region  and  not  reach  the  more 


92  University  of  California  Publications  in  Geology    [V°L-  7 

favorable  environment  of  Southern  California.  We  must,  then, 
almost  of  necessity  conclude  that  the  separation  of  the  two  faunas 
is  due  to  difference  in  time  rather  than  to  any  other  factor. 

The  two  horizons  have  in  common  with  the  Recent  North 
American  fauna  three  cathartine  genera,  viz.,  Cathartes,  Cath- 
arista,  and  Gymnogyps.  Catharista,  at  present  foreign  to  the 
immediate  vicinity,  is  represented  in  the  two  deposits  by  distinct 
species.  Gymnogyps  calif  ornianus  is  abundant  in  the  asphalt 
beds  and  in  the  Recent  fauna  of  a  region  including  and  extend- 
ing far  beyond  both  localities,  yet  the  genus  is  represented  in 
the  cave  deposits  only  by  a  distinct  species,  G.  amplus.  It  is 
hard  to  explain  how  the  cavern  deposits  could  have  been  inter- 
polated between  the  Rancho  La  Brea  horizon  and  the  Recent 
and  still  possess  two  distinctive  cathartine  forms  and  only  one, 
Cathartes  aura,  in  common  with  either  of  them. 

Distribution  of  Falconidae. — Palaeontology  has  added  mate- 
rially to  our  knowledge  of  this  group  in  at  least  two  respects, 
namely  in  our  concepts  of  the  former  distribution  of  its  members 
and  of  the  degree  of  adaptive  radiation  that  has  taken  place 
within  its  limits.  The  three  genera  Geranoaetus,  Morphnus,  and 
Polyborus,  limited  in  Recent  time  to  tropical  or  to  south  tem- 
perate America,  are  now  known  to  have  ranged  in  the  previous 
period  well  up  into  California.  Geranoaetus  went  as  far  north 
as  Hawver  Cave  and  the  other  two  as  far  as  Los  Angeles.  The 
larger  phase  of  Haliaetus,  which  is  limited  at  present  to  the 
northern  parts  of  North  America,  had  not  at  the  time  of  deposi- 
tion of  the  asphalt  beds  withdrawn  to  the  northward  as  a 
distinct  geographical  race.  The  remains  of  Haliaetus  leucoce- 
phalus  from  these  beds  embrace  in  their  range  of  variation  ex- 
tremes of  size  surpassing  at  either  end  of  the  scale  the  two 
existing  races,  H.  I.  alascanus  and  H.  I.  leucocephalus  now  geo- 
graphically distinct. 

As  illustrative  of  the  number  of  adaptive  radiations  of  the 
eagle  group  we  may  point  to  the  six  fossil  eagles  of  Marsh, 
Shufeldt,  and  Miller.  These  are  as  follows:  Aquila  sodalis,  A. 
pliogryps,  A.  dananus,  Morphnus  woodwardi,  Geranoaetus  grin- 
nelli,  and  G.  fragilis.  Besides  these  extinct  forms  there  were 
found  fossil  the  three  persisting  species  Aquila  chrysaetos, 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  93 

Haliaetus  leucoceplialus,  and  Geranoaetus  melanoleucus.  Aquila 
pliogryps  Shufeldt  is  described  from  a  single  bone,  the  basal 
phalanx  of  the  right  hallux.  The  species  is  considered  to  be 
slightly  larger  but  more  slender-limbed  than  Aquila  chrysaetos. 
The  material  representing  the  species  is  so  limited  that  no  clear 
impression  of  its  closer  relationships  can  be  formed.  Morph- 
nus  woodwardi  from  Rancho  La  Brea  may  well  have  been  such 
a  bird,  though  there  is  no  way  of  obtaining  more  than  the  sug- 
gestion of  similarity  from  the  fact  that  they  were  both  eagles 
of  slender  build.  The  statement  made  by  Shufeldt  is  that  Aquila 
pliogryps  was  slender  of  foot,  as  indicated  by  the  slightly  longer 
digits.  Morpknus  is  a  genus  of  long-shanked  eagles  with  rela- 
tively weak  feet,  as  indicated  by  the  size  of  the  trochleae.  The 
digits  certainly  must  have  been  much  smaller  in  Morplinus  wood- 
wardi than  in  Aquila  chrysaetos  or  in  A.  pliogryps. 

Shufeldt 's  species,  A.  sodalis,  is  founded  on  the  proximal 
part  of  a  tarsometatarsus.  The  specimen  is  figured  from  the 
anterior  aspect  drawn  to  natural  scale.  Compared  with  the 
Rancho  La  Brea  eagles,  A.  sodalis  corresponds  quite  closely  in 
size  with  Geranoaetus  fragilis,  the  smallest  of  the  group  there 
represented.  A.  sodalis  seems,  however,  to  be  of  an  entirely  dif- 
ferent nature  if  the  position  of  the  papilla  of  the  tibialis  anticus 
may  be  taken  as  indicative.  In  a  discussion  of  the  splendid 
series  of  eagle  tarsi  from  the  asphalt,  it  has  been  pointed  out 
by  the  author27  that  the  position  of  this  tubercle  seemed  to  bear 
a  very  definite  relation  to  the  slenderness  of  the  tarsus,  i.e.,  the 
long-shanked  forms  have  the  tubercle  placed  high  up  on  the 
shaft  of  the  bone.  Applying  this  principle  to  Shufeldt 's  figure 
of  A.  sodalis,  it  would  seem  that  the  Fossil  Lake  species  was 
not  of  the  same  group  of  eagles  as  the  more  southern  genera 
Morphnus  and  Geranoaetus  assembled  by  Ridgway  under  the 
caption  Morphni.  In  A.  sodalis  the  papilla  of  the  tibialis  anticus 
is  placed  farther  down  the  shaft  and  the  proximal  foramina  are 
separated  by  a  much  wider  space.  Unfortunately  the  charac- 
ter of  the  Itypotarsus  is  not  shown  in  Shufeldt 's  figure  of  Aquila 
sodalis  nor  is  an  accurate  impression  of  the  region  obtainable 
from  the  description.  It  seems  proper  to  consider  the  two  species 


Miller,  L.  H.,  Univ.  Calif.  Pub!.,  Bull.  Dept.  Geol.,  vol.  6,  p.  305,  1911. 


94  University  of  California  Publications  in  Geology    [V°L-  7 

described  by  Shufeldt  as  distinct  from  any  of  the  Rancho  La 
Brea  forms. 

Aquila  dananus  Marsh28  is  described  as  being  slightly  smaller 
than  the  existing  A.  ckrysaetos.  A  single  specimen  of  the  species 
was  taken  in  the  Loup  Fork  of  Nebraska.  It  consists  of  the 
distal  part  of  the  tibia  only  and  is  not  figured  by  Marsh  in  the 
original  description.  The  assignment  of  the  specimen  to  the 
genus  Aquila  is  proper  in  the  absence  of  any  feature  to  dis- 
tinguish it  from  that  genus.  The  suggestion  of  the  possible 
identity  of  one  of  the  Fossil  Lake  forms,  A.  sodalis,  with  Marsh's 
A.  dananus  is  made  in  Shufeldt 's  paper  but  that  author  con- 
siders the  case  improbable  on  the  score  of  smaller  dimensions  in 
the  former  species.  Geranoaetus  gracilis  Miller  from  the  asphalt 
is  the  smallest  of  the  fossil  eagles  from  California  and,  as  indi- 
cated above,  this  species  is  about  the  same  size  as  A.  sodalis  Shu- 
feldt. Marsh  himself  considered  the  Loup  Fork  specimen  to  be 
"nearly  as  large  as  the  Golden  Eagle,"  in  which  case  A.  dananus 
may  be  considered  as  probably  intermediate  in  size  between 
Aquila  chrysaetos  (Linnaeus)  and  Morphnus  woodwardi  Miller. 

The  only  other  fossil  falconids  from  American  localities  out- 
side of  California  are  Cope's  Palaeoborus  umbrosus,29  which 
Lucas30  very  properly  ascribes  to  the  Polyborinae,  and  two  species 
from  South  America  recorded  by  the  Argentine  palaeontologists, 
Moreno  and  Mercerat.31  Lagopterus  minutus  Mor.  and  Mer.  is 
the  smaller  of  these  two  South  American  species.  It  is  repre- 
sented by  an  almost  perfect  humerus  which,  according  to  the 
authors  describing  it,  is  intermediate  between  Buteo  and  Poly- 
borus,  with  the  preponderance  of  characters  relating  it  with 
Polyborus.  The  other  species,  Foetopterus  ambiguus,  Mor.  and 
Mer.,  is  considered  to  be  intermediate  between  Buteo  and  Cath- 
artes,  but  is  assigned  by  the  authors  to  the  Falconidae.  The 


28  Marsh,  O.  C.,  Am.  Journ.  Sci.,  vol.  2,  p.  125,  Aug.  1871. 

29  Cope,  E.  D.,  U.  S.  Geol.  Surv.  W.  of  100th  Merid.,  vol.  4,  pt.  2,  p.  287, 
1876. 

sozittel,  Textbook  of  Palaeontology,  trans,  by  Eastman,  vol.  2,  p.  277, 
1902. 

si  Moreno  and  Mercerat,  Palae.  Argentina,  An.  Mus.  La  Plata,  vol.  1, 
1891. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  95 

more  intimate  relationships  of  the  forms  are  not  discussed  by 
the  authors. 

LIST  OF  SPECIES  ASSIGNED  TO  THE  SUBORDER  FALCONES  THAT  ARE  KNOWN 

TO  OCCUR  AS  FOSSILS  IN  NORTH  AMERICA 

Species  marked  with  the  asterisk  are  extinct  or  are  no  longer  repre- 
sented in  the  region.  Species  marked  with  the  double  asterisk  are  con- 
sidered to  show  their  closest  relationship  to  forms  at  present  more  southern 
in  their  distribution. 

Elanus  leucurus  (Vieillot),  Eancho  La  Brea. 
Circus  hudsonius   (Linnaeus),  Eancho  La  Brea,  Fossil  Lake. 
**Circus  sp.   (smaller  than  hudsonius),  Rancho  La  Brea. 

Aquila  chrysaetos    (Linnaeus),  Rancho  La  Brea. 
*Aquila  sodalis  Shufeldt,  Fossil  Lake. 
*Aquila  pliogryps  Shufeldt,  Fossil  Lake. 
*Aquila  dananus  Marsh,  Loup  Fork. 

Haliaetus  leucocephalus   (Linnaeus),  Rancho  La  Brea. 
**Morphnus  woodwardi  Miller,  Rancho  La  Brea. 
**Geranoaetus  grinnelli  Miller,  Rancho  La  Brea. 
**Geranoaetus  melanoleucus  Auct.  (?),  Hawver  Cave. 
**Geranoaetus  fragilis  Miller,  Rancho  La  Brea. 

Buteo  borealis   (Gmelin),  Rancho  La  Brea,  Potter  Creek  Cave. 
Buteo  swainsoni   (?)   Bonaparte,  Samwel  Cave. 
*Buteo,  sp.   (larger  than  Archibuteo),  Rancho  La  Brea. 
Archibuteo   ferrugineus    (Lichtenstein),   Hawver   Cave. 
Falco  peregrinus  Tunstall,  Rancho  La  Brea,  Potter  Creek  Cave. 
*  Falco,  sp.   (smaller  than  peregrinus),  Rancho  La  Brea. 
Falco  sparverius  Linnaeus,  Rancho  La  Brea,  Samwel  Cave  and  Potter 

Creek  Cave. 

**Polyborus  tharus  Auct.,  Rancho  La  Brea. 
*Palaeoborus  umbrosus   (Cope),  Loup  Fork  of  New  Mexico. 
Accipiter  velox  (Wilson),  Samwel  Cave. 

The  species  of  Circus  remaining  undetermined  is  a  form 
smaller  than  the  North  American  C.  hudsonius.  It  is  not  named 
in  this  paper  since  no  opportunity  has  been  presented  to  com- 
pare it  with  the  South  American  species  Circus  cinereus  and 
C.  maculosa.  The  last  two  species,  it  seems,  are  smaller  than 
C.  hudsonius  and  possibly  the  asphalt  specimens  referred  to  the 
indeterminate  species  are  of  a  form  identical  with  the  one  or 
the  other. 

The  material  from  Rancho  La  Brea  representing  Polyborus 
is  abundant  and  embraces  most  parts  of  the  appendicular  skele- 
ton and  the  beak,  including  the  characteristic  nareal  region. 
All  this  material  was  compared  very  carefully  with  the  Recent 


96  University  of  California  Publications  in  Geology    [VOL.  > 

phase  of  Polyborus  tharus  as  represented  by  a  single  specimen 
from  Argentina.  As  no  appreciable  difference  could  be  noted, 
the  fossil  form  is  referred  to  the  existing  species,  P.  tharus. 

Anomalies  in  Distribution. — According  to  Ridgway32  the 
present  distribution  of  Polyborus  tharus  is  from  Amazonia  south- 
ward through  South  America.  The  bird  thus  reaches  in  the 
Argentine  and  the  Patagonian  climates  a  set  of  conditions  as 
rigorous  as  any  that  it  would  be  liable  to  experience  in  the 
northern  hemisphere  in  the  latitude  of  Los  Angeles.  The  ex- 
tremes of  climate  due  to  the  presence  of  the  ice  sheet  is  thought 
by  Allen  to  have  given  rise  to  the  periodical  movements  of  birds 
which  finally  merged  into  the  present  seasonal  migration.33 
Would  not  a  plausible  explanation  be  that  the  polyborine  under 
discussion  was  driven  southward  by  the  cold  of  the  glacial  epoch 
but  failed  to  respond  to  the  later  amelioration  of  climate  because 
of  a  nature  less  susceptible  to  the  development  of  a  migratory 
instinct  and  therefore  remained  in  the  lower  latitudes  or  below 
the  tropics?  No  record  of  the  true  Polyborinae  is  yet  found 
in  the  deposits  of  the  southern  hemisphere  to  correspond  with 
the  Pliocene  form,  Palaeoborus  umbrosus  (Cope),  from  New 
Mexico  or  to  extend  the  occurrence  of  the  group  even  back  to 
the  Pleistocene,  as  the  Bancho  La  Brea  material  does  so  abund- 
antly for  the  northern  hemisphere.  If,  on  this  slender  thread 
of  negative  evidence,  we  assume  that  the  group  arose  in  the  North 
Temperate  zone,  the  explanation  suggested  above  seems  a 
plausible  one. 

Geranoaetus  and  Circus  present  cases  similar  to  that  of  Poly- 
borus, while  Morphnus  differs  in  that  the  genus  is  at  present 
limited  to  the  tropics  and  probably  never  reaches  a  southward 
distribution  which  would  correspond  climatically  with  the  region 
of  Hawver  Cave  or  of  Los  Angeles. 

These  two  cases  of  Polyborus  and  Morphnus  mentioned  above 
are  typical  of  as  many  classes  of  change  in  distribution  since 
the  formation  of  the  various  Pleistocene  deposits.  Parallel  with 
Polyborus  there  appear  the  following  fossil  forms  whose  nearest 


32  Ridgway,  R.,  U.  S.  Geol.  &  Geog.  Surv.  Terr.,  vol.  1,  No.  6,  p.  451,  1876. 
ss  Allen,  J.  A.,  The  geography  and  distribution  of  birds,  Auk.  vol.  10, 
No.  2,  April,  1893. 


Miller:  Pacific  Coast  Avian  Palaeontology  97 

relatives  occur  in  the  southern  hemisphere  at  a  latitude  corres- 
ponding with  the  region  of  deposit  in  the  northern  hemisphere. 

Fossil  Species  Nearest  Living  Eelative 

Phoenicopterus  copei  Shufeldt Phoenicopterus  ruber  ?  Linnaeus 

Cieonia  maltha  Miller Euxenura  maguari    (Temm.) 

Mycteria  americana  Linnaeus  Mycteria  americana  Linnaeus 

Jabiru  mycteria   (Lichtenstein) Jabiru  mycteria  author 

Catharista  occidentalis  Miller Catharista  urubu  (Vieillot) 

Sarcorhamphus  clarki  Miller Sarcorhamphus  gryphus  Auct. 

Circus,  sp Circus  cenereus  or  C.  maculosus 

Geranoaetus  melanoleucus  Auct Geranoaetus  melanoleucus  Auct. 

Geranoaetus  fragilis  Miller 

Polyborus  tharus  Auct Polyborus  tharus  Auct. 

Cases  parallel  with  Morphnus  in  having  their  nearest  related 
Recent  phase  limited  to  more  tropical  zones  are  as  follows : 

Fossil  Species  Nearest  Living  Eelative 

Pavo  californicus  Miller Pavo   cristatus  or  Meleagris  ocellatus 

Morphnus  woodward!  Miller Morphnus   guianensis   Auct. 

Geranoaetus  grinnelli  Miller Morphnus   guianensis   Auct. 

Micropallas  whitneyi  (Cooper) Micropallas  whitneyi  (Cooper) 

Geococcyx  (?),sp .Neomorpha  geoffroyi    (Temm.) 

One  of  the  striking  features  in  the  study  of  so  representative 
a  series  of  deposits,  all  of  so  nearly  the  same  age  as  are  the 
bird-bearing  deposits  of  the  Pacific  Coast,  is  the  total  absence 
of  certain  forms  which  one  would  expect  to  find  therein.  While 
it  is  conceded  that  negative  evidence  in  palaeontology  is  a  frail 
peg  upon  which  to  hang  an  opinion,  yet  the  negation  may  be  so 
pronounced  and  so  uniformly  persistant  that,  in  some  cases  at 
least,  the  only  conclusion  possible  is  that  species  did  not  occur 
in  the  region  during  the  time  of  deposition. 

The  particularly  favorable  conditions  offered  at  Rancho  La 
Brea  for  the  trapping  of  vultures  and  eagles  has  been  commented 
upon  in  a  previous  paper  on  the  condors.  There  was  exposed 
at  that  place  during  an  indefinite  period  a  more  or  less  con- 
stantly baited  trap  which  was  unusually  attractive  to  both  vul- 
ture and  eagle.  It  was  automatic  in  its  operation,  effective  in 
its  hold  upon  the  victim,  and  almost  ideal  in  the  preservation  of 
its  catch,  the  remains  of  which  were  sealed  from  the  air  in  liquid 
asphalt  while  still  in  the  flesh.  The  entire  collection  of  raptorial 
remains  includes,  however,  no  specimen  of  the  royal  vulture 
(Gyparchus  papa)  or  of  the  harpy  eagle  (Thrasaetus  harpy  a}, 


98  University  of  California  Publications  in  Geology    [V°L-  7 

both  of  which  occur  at  present  along  the  Mexican  border  within 
fifteen  degrees  of  the  latitude  of  Los  Angeles. 

The  collection  of  wading  birds  from  the  coast,  while  not  rich 
in  point  of  numbers,  embraces  a  goodly  variety.  Jabiru,  Myc- 
teria,  Ciconia,  Grus,  Ardea,  and  Phoenicopterus  are  represented ; 
yet  there  is  no  record  of  the  spoonbill  (Ajaia)  or  of  the  ibis 
(Guard),  both  of  which  have  been  taken  in  the  flesh  well  to 
the  northward  of  Rancho  La  Brea. 

Grouse,  quail,  and  meleagrines  have  been  taken  in  various 
of  the  deposits  under  discussion;  yet  we  find  there  none  of  the 
cracid  birds  such  as  Ortalis  which  occurs  at  present  along  the 
Rio  Grande  valley  of  Texas. 

The  absence  of  the  above-mentioned  species,  particularly  the 
Raptores,  from  all  the  bird-bearing  deposits  thus  far  known  to 
North  America  becomes  very  striking  in  view  of  the  large  num- 
ber of  instances  recorded  of  the  southward  retraction  of  species 
and  genera  since  the  Pleistocene  period.  It  is  possible  that  the 
forms  mentioned  above  were  more  sensitive  to  the  cold  and  were 
driven  southward  before  the  deposition  of  the  Pleistocene  strata 
thus  far  explored,  or  that  they  were,  on  the  other  hand,  more 
tropical  species  that  have  only  in  Recent  time  diffused  north- 
ward to  their  present  range.  Gyparchus  is  reported  from  the 
Pleistocene  caves  of  Brazil  by  Winge  (op.  cit.)  which  fact  would 
support  the  latter  hypothesis.  Polyborus  ckeriway  would  fall 
in  the  same  category  with  Gyparchus,  being  represented  in  the 
asphalt  by  its  close  relative  Polyborus  tharus.  The  same  is  per- 
haps true  of  the  Recent  species  of  Geococcyx  found  in  the  Son- 
oran  zone  of  California  at  the  present  time  but  represented  in 
the  asphalt  only  by  a  longer-shanked  form  which  can  scarcely  be 
considered  as  the  direct  ancestor  of  the  living  Geococcyx  cali- 
fornianus.  The  species  from  the  asphalt  may  be  identical  with 
one  of  the  species  of  Neomorpha  from  South  America,  comparison 
between  them  having  been  thus  far  impossible. 

Approximately  eighty  species  of  true  columbine  birds  inhabit 
the  Americas  today  and  many  of  the  species  are  forms  which 
feed  on  the  ground  and  which  congregate  about  water  holes 
to  drink;  yet  there  is  no  specimen  in  all  the  material  examined 
which  is  referable  to  this  group.  The  commonest  species  in  the 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  99 

coast  region  today  is  the  turtle-dove  (Zanaidura  macroura),  a 
bird  of  wide  distribution  over  the  Austral  region  and  even  to 
the  tropics.  Its  habits  and  its  abundance  are  such  that  one  can 
scarcely  concede  as  possible  that  it  could  have  been  present 
during  the  deposition  of  the  Pleistocene  beds  of  Rancho  La  Brea 
and  yet  not  be  preserved  as  a  fossil. 

Palamedea  and  Cariama  have  in  their  present  home  in  South 
America  a  distribution  and  habits  not  unlike  those  of  the  stork, 
Euxenura.  Both  groups  are,  however,  absent  from  the  fossil 
collections.  The  peculiarly  isolated  positions  which  these  birds 
occupy  in  the  scheme  of  classification,  as  well  as  the  measure  of 
uncertainty  as  to  their  proper  location  systematically,  makes  any 
light  that  palaeontology  might  throw  upon  the  subject  especially 
desirable.  Most  careful  search  was  made  therefore  to  see  if  any 
part  of  the  skeleton  of  these  birds  had  been  preserved,  but 
nothing  was  found  that  resembled  either  species  in  the  smallest 
degree. 

The  parrot  order,  abundant  a  few  degrees  to  the  southward, 
is  unrepresented  in  the  deposits.  This  may  be  due  to  the  fact 
that  the  only  forest  fauna  which  we  have  preserved  to  us  (cavern 
deposits)  is  of  Upper  Sonoran  and  lower  Transition  zones,  and 
thus  local  conditions  may  have  been  unfavorable  for  these  birds. 
On  the  other  hand,  as  suggested  in  the  case  of  Ortalis,  they  may 
have  been  driven  southward  before  the  deposition  of  any  of 
the  beds  thus  far  explored. 

All  trace  of  true  struthious  birds  is  lacking  in  the  collec- 
tions also.  The  northward  diffusion  of  such  forms  as  the  eden- 
tates and  Hydrockoerus  among  the  mammals,  the  presence  since 
early  Pleistocene  time  of  rheas  in  South  America,  the  occurrence 
of  tridactyl  struthionids  in  the  Pliocene  of  northern  India,  and" 
of  Struthiolithus  in  the  superficial  deposits  of  northern  China, 
increase  the  probability  that  some  day  the  discovery  of  true 
struthious  birds  in  North  America  will  be  announced.  The  most 
potent  factors  that  would  bring  about  such  distribution  are 
first,  the  possible  northward  diffusion  of  rheids  along  with  eden- 
tate mammals  and,  second,  the  passage  of  Struthiolithus  or  its 
relatives  along  the  line  of  proboscidean  invasion  from  Asia  by 
way  of  the  land  bridge  to  Alaska. 


100         University  of  California  Publications  in  Geology    [VOL.  7 

The  earliest  occurrence  of  rheids  in  South  America  is  in 
strata  now  referred  to  the  Pleistocene  (the  Pampean  of  Monte 
Hermosa).  If  the  group  had  reached  that  continent  by  way 
of  the  Antarctic  at  an  earlier  time,  their  bones  would  probably 
be  found  with  the  primitive  mammals  supposed  to  have  been 
derived  from  Australia  and  known  to  us  from  the  Santa  Cruz 
beds.  The  rheas  with  their  true  struthious  characters  could 
hardly  have  originated  de  novo  in  South  America;  hence  the 
conclusion  that  they  entered  from  the  north,  as  did  the  true 
cats,  deer,  elephants  and  other  mammals  of  northern  or  Old 
World  origin. 

Cope's  discovery  of  Diatryma94  in  the  Wahsatch  Eocene  of 
New  Mexico  was  at  first  considered  as  fixing  a  very  early  date 
for  the  group  of  Struthiones  in  the  New  World.  Lucas,35  how- 
ever, places  this  unique  specimen  in  the  group  of  Stereornithes 
with  the  great  Phororkacos  of  South  America  (Miocene  of  Santa 
Cruz).  A  wide  gulf  exists  between  the  ostriches  and  these 
South  American  phororhacids.  The  latter  are  more  probably  a 
local  development  brought  out  in  response  to  the  peculiar  con- 
ditions prevailing  there  in  Tertiary  time.  There  existed  in  South 
America  no  large  carnivores  among  mammals  until  the  northern 
incursion  of  machaerodonts  and  the  true  felines  in  relatively  late 
geological  time.  Edentates  were  left  free  to  develop  to  the 
tremendous  extent  noticeable  in  the  South  American  Tertiary 
and  Quaternary.  In  this  region  of  low  pressure  among  mam- 
mals there  developed  unrestrained  the  predatory  bird  Phoro- 
rhacos,  to  occupy  a  bionomic  place  like  that  of  the  mammalian 
carnivore.  The  reference  by  Lucas  of  the  North  American  Dia- 
tryma to  the  Stereornithes  is  tentative.  He  states  the  case  in 
these  words  in  part:  "Still  there  are  sufficient  resemblances  be- 
tween the  two  to  warrant  the  suggestion  that  if  material  comes 
to  light  it  will  be  found  that  the  affinities  of  Diatryma  are  with 
the  Stereornithes  and  not  with  the  Dromaeognathae. " 

In  view  of  the  indeterminate  character  of  the  single  specimen 
of  Diatryma  where  its  relationship  between  two  such  distinct 


34  Cope.  E.  D.,  U.  S.  Geol.  Surv.  Terr.  W.  of  100th  Merid.,  vol.  4,  pt.  2, 
p.  69,   1876. 

35  Lucas,  F.  A.,  Proc.  U.  S.  Nat.  Mus.,  vol.  24,  p.  545,  1903. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  101 

groups  as  the  Struthiones  and  the  Stereornithes  are  in  question, 
it  would  seem  that  the  chief  value  of  Cope's  discovery  is  to 
show  us  that  a  group  of  gigantic  terrestrial  birds  can  inhabit 
a  region  and  leave  almost  no  trace  of  their  occupation  of  that 
part  of  the  globe.  The  same  fact  is  pointed  out  by  Eastman30 
in  his  discussion  of  Struthiolithus  and  the  distribution  of  the 
Dromaeognathae.  Before  the  discovery  of  this  species  in  the 
superficial  deposits  in  the  mountainous  regions  of  northern 
China  no  one  would  have  surmised  that  this  great  area  to  the 
north  of  India  was  ever  inhabited  by  struthious  birds.  Why  not 
expect,  then,  with  perfect  propriety,  that  some  day  the  path  of 
immigration  of  Rhea  into  South  America  may  be  traced  in  yet 
undiscovered  deposits  of  North  America  ? 

The  other  principle  which  encouraged  the  search  for  rheaids 
in  the  asphalt,  that  of  a  northward  migration  of  southern  forms 
in  the  Pleistocene,  is  applicable  whether  Rhea  be  considered  a 
product  of  the  southern  continent  or  not.  Among  mammals  we 
have  the  northward  diffusion  of  the  various  edentates  and 
Hydrochoerus,  which  may  be  considered  products  of  southern 
soil,  and  we  have  also  a  re-entrance  from  the  south  of  certain 
forms  which  are  Neogaeic  by  adoption.  For  example,  we  may 
look  upon  Didelphys  as  having  performed  such  migration.  The 
objection  might  be  raised  that  the  tropical  belt  would  act  as  a 
barrier  preventing  the  plains-dwelling  RJiea  from  retracing  its 
steps,  but  such  an  objection  is  reduced  to  questionable  validity 
by  the  presence  of  true  rheids  in  the  cavern  deposits  of  Brazil. 

The  following  is  a  list  of  lipotypes  which  are  considered  by 
the  author  as  of  particular  interest: 

LIST  OF  LIPOTYPES 

Gavia,  sp.  Palamedeidae — all    species 

"Gyparchus  papa  Auct.  Cariamidae — all  forms 

Thrasaetus  harpya  Auct.  Phororhacidae — all  species 

Polyborus  cheriway  (Jaquin)  Gaura,  sp. 

Cracidae— all    species  Plegadis,   sp. 

Columbae — all    species  Ajaia,   sp1. 

Psittaci — all    species  Geococcyx  calif ornianus  (Lesson) 


36  Eastman,  C.  R.,  Bull.  Mus.  Comp.  Zool.  Harvard  Coll.,  vol.  32,  p. 
127-144,  1898. 


102         University  of  California  Publications  in  Geology    [VOL.  7 

Possible  Influences  Conditioning  Present  Distribution  of  Cer- 
tain Groups. — In  considering  the  relation  of  past  to  present  dis- 
tribution of  American  birds,  at  least  two  principles  present  them- 
selves in  explanation  of  the  apparent  southward  retraction  of 
certain  forms  since  Pleistocene  time.  The  first  is  typified  by  the 
case  of  Polyborus  tharus.  May  this  species  not  have  been  driven 
southward  across  the  equator  after  the  time  of  formation  of 
the  asphalt  deposits  by  the  advance  of  a  cold  period  such  as  sent 
the  mammals  of  the  Ovibos  zone  as  far  south  as  Big  Bone  Lick 
and  Conard  Fissure? 

Extremes  of  climate  due  to  the  presence  of  the  ice  sheet  are 
thought  by  Allen37  to  have  given  rise  to  the  periodical  move- 
ments of  birds  which  finally  merged  into  the  present  seasonal 
migration.  The  polyborine  under  discussion  may  thus  have  been 
driven  southward,  but  lacked  the  incipient  migratory  instinct  and 
furthermore  failed  to  return  northward  upon  the  amelioration 
of  the  climate.  This  failure  may  have  been  due  to  the  presence 
of  more  virile  species  blocking  the  return  path,  or  it  may  have 
been  due  to  the  limiting  tendency  of  the  torrid  zone  which  it 
would  have  had  to  recross  in  a  return  to  the  north.  No  record 
of  the  true  Polyborinae  has  yet  been  found  in  the  deposits  of 
the  southern  hemisphere  to  correspond  with  the  Pliocene  Palaeo- 
borus  of  New  Mexico  or  to  extend  the  occurrence  of  the  group 
even  back  to  the  Pleistocene,  as  the  Eancho  La  Brea  material 
does  so  abundantly  for  the  northern  hemisphere.  If,  on  this 
slender  thread  of  negative  evidence,  we  assume  that  the  group 
arose  in  the  North  Temperate  Zone,  the  explanation  suggested 
above  seems  a  plausible  one.  The  distribution  of  Circus,  Geran- 
oaetus,  Sarcorhamphus,  and  Euxenura  would  further  uphold  this 
view  of  the  question.  These  birds  are  typically  of  the  southern 
hemisphere  in  latitudes  to  the  south  of  the  tropics  or  at  high 
elevations  and  the  Tierra  Caliente  would  act  as  a  more  or  less 
effective  barrier  to  their  northward  dissemination. 

The  second  hypothesis  offered  is  that  the  returning  annual 
isotherm  has  never  yet  reached  the  point  at  which  it  stood  during 
the  deposition  of  the  fossil  remains.  Sinclair  (Op.  cit.,  p.  19) 
links  the  Potter  Creek  Cave  deposits  pretty  closely  with  the 


37  Allen,  J.  A.,  The  Auk,  vol.  X,  No.  2,  Apr.  1893. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  103 

Upper  San  Pedro  series  of  marine  deposits  and  the  San  Pablo 
Bay  oyster  beds  at  Rodeo.  These  shell  deposits  are  considered  by 
western  palaeontologists  to  represent  a  time  of  higher  average 
annual  temperatures  than  prevail  in  the  region  at  present.  The 
cases  of  Morphnus,  Micropallas,  Geococcyx  (')  and  Pavo  make 
a  strong  aggregate  in  favor  of  this  theory.  To  harmonize  the 
cases  of  Circus,  Polyborus,  Sarcorhamphus,  Geranoaetus  and 
Ciconia  with  those  of  the  more  tropical  species,  it  would  be  neces- 
sary to  assume  nothing  further  than  that  these  forms,  since  the 
partial  amelioration  of  the  climate,  had  developed  powers  of 
resistance  to  cold  and  had  extended  their  ranges  to  the  southward 
instead  of  remaining  intertropical  species.  The  extension  of 
range  took  place  from  the  tropics  southward  instead  of  to  the 
northward  again  because  of  overcrowded  conditions  in  the  north. 
The  advance  of  arctic  cold  toward  the  equator  would  drive  north- 
ern animals  into  narrower  and  narrower  quarters,  while  the 
forms  of  the  southern  hemisphere,  under  like  encroachment  of 
the  antarctic,  would  experience  the  opposite  effect.  The  conver- 
gence of  all  the  Boreal  species  into  the  Austral  on  the  continent 
of  North  America  would  be  in  effect  like  crowding  the  basal  con- 
tents of  a  cone  into  its  apex.  The  result  would  be  an  enormous 
intensification  of  the  natural  attrition  of  species  upon  species 
with  a  resultant  stimulus  to  the  surviving  form.  In  the  southern 
hemisphere  conditions  would  be  reversed  and  the  advance  of 
polar  cold,  whether  synchronous  with  or  alternating  with  the 
northern  fluctuations,  would  have  much  less  serious  effect.  As- 
suming the  various  faunal  zones  to  be  fully  populated,  the  driv- 
ing of  the  Patagonian  fauna  into  the  wide  expanse  of  Argentina 
and  southern  Brazil  would  serve  to  dilute  greatly  the  Boreal 
fauna  without  materially  disturbing  the  Austral.  A  form  that 
had  been  obliged  to  flee  the  rigorous  conditions  resulting  from 
an  advance  of  the  cold  in  North  America  might  find,  upon  the 
return  of  milder  conditions,  that  the  path  of  least  resistance  to 
expanding  range  from  the  tropics  led  toward  the  south. 

Bird  Remains  as  Indicators  of  Climatic  Conditions. — Certain 
appearances  in  the  deposits  at  Rancho  La  Brea  might  be  inter- 
preted as  evidence  that  the  climate  during  deposition  of  the  beds 
was  warmer  and  more  moist  than  it  is  at  present  in  the  region. 


104         University  of  California  Publications  in  Geology    [VoL-  7 

The  fauna  is  certainly  a  rich  one  and  embraces  a  considerable 
variety  of  ungulates  of  large  size  which  were  dependent  on  a 
goodly  supply  of  grass  and  browse.  Purely  local  conditions  of 
dainage  may,  however,  have  brought  about  such  a  condition.  In 
the  fickle  streams  of  the  southwest  such  change  of  bed  may  occur 
in  a  single  season  and  a  deposit  laid  down  under  conditions  of 
abundant  moisture  amounting  almost  to  a  peat  formation  may 
be  left  high  and  dry  after  a  severe  freshet  to  suffer  a  reversion 
to  almost  desert  condition.  Relatively  few  of  the  anserines  are 
found  in  the  collections  from  the  asphalt.  Geese  of  the  Recent 
species  become  almost  upland  forms  during  the  rainy  season 
when  grass  is  abundant.  Euxenura  is,  according  to  Hudson's 
account  in  Naturalist  in  La  Plata,  a  plains-dwelling  form  of  the 
open  pampa  at  some  times  of  the  year.  The  sand-hill  crane, 
Grus  canadensis,  is  notably  a  plains  feeder  in  the  winter  and 
spring,  while  the  great  blue  heron,  Ardea  herodias,  has  been 
seen  by  the  author  on  the  dry  hillsides  in  midsummer  seemingly 
in  pursuit  of  grasshoppers.  The  presence  of  these  birds  in  the 
asphalt  in  the  limited  numbers  found  is  not  then  a  positive 
indication  of  open  water  or  of  even  marshy  ground.  The  water- 
worn  fragments  of  wood  and  the  leaves  in  bedded  deposit  are 
such  as  occur  in  small  steams  of  the  region  today  when  the 
streams  may  be  more  or  less  intermittant.  A  rich  and  varied 
mammalian  fauna  is  taken  by  some  writers  as  an  indication  of 
mild  climatic  conditions.  Such  conclusion  seems  scarcely  war- 
ranted, however,  in  view  of  the  present  conditions  in  the  desert 
parts  of  the  world.  The  writer  found  deer  abundant  on  the 
open  and  thorny  desert  of  Lower  California  in  the  region  of 
Cape  San  Lucas.  On  the  mainland  of  Mexico,  in  the  desert  of 
Sonora,  deer,  peccary,  and  mountain  sheep  are  abundant.  The 
accounts  by  Roosevelt  of  game  distribution  in  Africa  indicate 
an  abundance  and  a  great  variety  of  game  in  almost  desert 
regions  of  that  continent.  On  the  Mohave,  the  Colorado,  and 
the  great  Nevada  deserts,  the  most  ephemeral  pools  of  water, 
even  when  highly  impregnated  with  alkaline  salts,  are  the  resort 
of  multitudes  of  waterfowl,  while  Cope  and  Shufeldt  describe 
abundant  life  in  the  region  near  Fossil  Lake  on  the  Oregon 
Desert. 


1912J  Miller:  Pacific  Coast  Avian  Palaeontology  105 

There  is  some  very  credible  evidence  that  the  mammals  en- 
trapped in  the  asphalt  pools  were  in  part  attracted  to  the  locality 
by  water.  Over  the  top  of  the  asphalt  layer  there  may  accumu- 
late after  a  shower  a  stratum  of  fairly  pure  rain  water,  so  little 
does  the  viscid  asphalt  mix  with  the  water.  Such  an  accumula- 
tion remains  in  the  impervious  basins  until  evaporated  by  the 
heat  of  the  sun,  without  loss  by  seepage  through  the  oil-impreg- 
nated earth.  Pools  of  water  suitable  for  the  use  of  cattle  and 
horses  thus  remain  impounded  in  natural  reservoirs  after  adja- 
cent streams  have  vanished.  Natural  reservoirs  are  of  such  im- 
portance in  the  southwestern  deserts  as  to  have  received  the  local 
Spanish  name  of  "tinajas,"  and  wild  mammals  of  the  desert 
come  from  long  distances  to  drink  at  them.  Such  conditions 
would  tend  to  concentrate  the  remains  of  mammals  of  a  poorly 
watered  region  and  furnish  the  asphalt  trap  with  scores  of 
victims  which  otherwise  would  have  escaped.38 

Summing  up  the  evidence  of  a  warm,  moist  climate  during 
the  Pleistocene,  we  have  the  following  points,  all  of  which  are 
inconclusive : 

1.  The  presence  of  species  whose  nearest  relatives   are   at 
present  more  tropical  in  distribution. 

2.  The  presence  of  an  abundant  fauna  which  is  suggestive 
of  favorable  conditions  of  climate. 

3.  The  presence  of  aquatic  species  and  of  waterworn  chips 
laid  down  in  places  now  dry  but  showing  no  great  changes  in 
topography. 

4.  The  suggestion  that  the  mammals  of  Rancho  La  Brea  were 
in  some  measure  led  to  the  region  by  the  presence  of  water. 

Time  Relations  as  Suggested  by  a  Study  of  Bird  Remains. — 
Osborn  divides  the  Pleistocene  period  into  three  great  time 
subdivisions,  namely,  Pre-Glacial,  Glacial-  and  Post-Glacial.39 
The  Glacial  again  shows  evidence  of  division  into  five  periods 
of  fluctuation,  during  which  the  ice  cap  oscillated  northward 
and  southward  with  the  changing  isotherms.  The  period  also 
represents  a  time  of  high  elevation  of  the  land  surface  in  general 


ss  See  Darwin,  C.,  Journal   of  Voyage  of  H.M.S.   Beagle,   1845    (New 
ed.  1909),  pp.   128-130. 

so  Osborn,  H.  F.,  The  Age  of  Mammals.     New  York,  1910. 


106         University  of  California  Publications  in  Geology    [V°L-  7 

as  compared  with  the  Pre-Glacial.  The  Post-glacial  epoch  was 
characterized  by  an  ameliorated  climate  and  a  depression  of  the 
land  surface.  Great  river  floods  and  large  lakes  were  the  result 
of  this  amelioration,  and  extensive  fluviatile  and  lacustrine  de- 
posits appear,  while  the  previously  restricted  species  of  verte- 
brates spread  out  over  parts  of  the  country  that  were  formerly 
covered  by  the  ice  cap. 

The  faunas  of  the  time  are  divided  by  Osborn  into  three  life- 
zones  which  are  distributed  through  the  Pleistocene,  but  do  not 
coincide  with  the  three  time  divisions  as  given  above.  They  do 
not  necessarily  represent  consecutive  faunas,  but  rather  faunas 
from  different  topographic  divisions  which,  in  some  respects, 
overlap  each  other,  though  in  the  main  consecutive.  Charac- 
teristic mammals  have  given  the  names  to  these  zones  as  follows : 
Equus  Zone,  a  plains  fauna  partly  earlier  than  and  partly 
synchronous  with  the  second,  the  Megalonyx  Zone,  which  was 
a  forest  and  meadow  fauna  mainly  of  mid-Pleistocene  time.  The 
third,  or  Ovibos  Zone,  is  an  impoverished  fauna,  perhaps  cor- 
responding with  the  Arctic  and  Tundra  period  of  Europe  and 
synchronous  with  the  last  great  glacial  advance,  the  period  of 
maximum  glaciation,  which  is  recorded  in  the  great  terminal 
moraine. 

RELATIONS    OF    SEVERAL    PLEISTOCENE    MAMMALIAN    HORIZONS;    ADAPTED 

FROM   OSBORN 

Equus  Zone  Megalonyx  Zone 

6 — Kansas    Pleistocene,    several  9 — Big  Bone  Lick,  Ken. 

localities.  8— Samwel  Cave,  Calif. 

5— Lake  Lahontan,  Nev.  7— Potter  Creek  Cave,  Calif. 

4— Fossil   Lake,    Ore.  6— Washtucna  Lake,  Wash. 

3 — Eock  Creek,   Texas.  5 — Rancho  La  Brea,  Calif. 

2 — Hay  Springs,  Neb.  4 — Ashley  Eiver,   S.  Carolina. 

1 — Peace    Creek,    Fla.,    Late    Plio-  3 — Frankstown  Cave,  Penn. 

cene  or  Early  Pleistocene.  2 — Port  Kennedy  Cave,  Penn. 

1 — Afton  Junction,   Iowa. — 1st  in- 
terglacial   stage. 

Ovibos  Zone 
4 — -Alaska  Ground  Ice. 
3 — Conard  Fissure,  Ark. 
2 — Scattered  middle  west. 
1 — Big  Bone  Lick,  Ken. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  107 

The  exact  time-relations  between  the  several  faunas  is  not 
determinate,  and  the  overlap  of  one  column  upon  another  is 
purposely  indefinite.  The  Equus  fauna  is  considered  in  part 
older  than  the  Megalonyx  fauna  and  this  in  turn  than  the 
Ovibos. 

It  must  be  stated  also  that  the  study  of  mammalian  remains 
from  Rancho  La  Brea,  from  the  caves  of  California,  and  from 
Fossil  Lake,  Oregon,  is  still  being  actively  pursued  and  the  list 
of  species  revised.  Any  statement  of  time-relations  must  be 
considered  as  purely  tentative.  Few  investigators  have  had  so 
wide  and  so  comprehensive  an  acquaintance  with  the  mammalian 
palaeontology  of  North  America  as  has  Professor  Osborn;  hence 
it  is  considered  in  this  connection  that  his  chronological  arrange- 
ment of  the  various  mammal-bearing  horizons  represent  the 
truth  as  nearly  as  we  have  yet  arrived  at  it. 

It  will  be  noted  that  the  Fossil  Lake  horizon  is  placed  by 
him  midway  in  the  tabulation  of  the  Equus  Zone  fauna  while 
Rancho  La  Brea  and  the  caves  occupy  the  middle  and  upper 
parts  of  the  Megalonyx  Zone.  Thus  Fossil  Lake  is  to  be  con- 
sidered as  the  earliest  Pleistocene  horizon  on  the  coast  produc- 
tive of  avian  remains. 

If  we  apply  the  criterion  of  percentage  of  extinct  forms, 
the  evidence  furnished  by  the  avian  remains  would  indicate 
a  different  time-relation  than  that  suggested  by  Professor  Os- 
born. The  various  horizons  here  discussed  show  the  following 
sequence  when  arranged  according  to  the  percentage  of  Recent 
species  of  birds  recorded  fossil: 

Eancho  La  Brea 60%  still  living 

Fossil   Lake   66%  still  living 

Potter  Creek  Cave  68%  still  living 

Samwcl  Cave  72%  still  living 

Hawver  Cave  79%  still  living 

The  application  of  this  principle  in  the  case  of  fossil  birds 
seems,  however,  less  accurate  than  in  the  case  of  mammals  when 
we  consider  the  migratory  nature  of  many  bird  species.  The 
Fossil  Lake  fauna  according  to  this  basis  of  estimate  would 
appear  to  be  younger  than  that  of  Rancho  La  Brea.  A  glance 
at  the  list  of  species  from  Fossil  Lake  shows,  however,  the  large 


108         University  of  California  Publications  in  Geology     [VOL.  7 

percentage  of  migratory  forms  such  as  the  anserines  and  the 
pygopodes.  These  birds  by  their  migratory  habits  are  rendered 
largely  immnne  to  the  effects  of  climatic  change  that  might 
have  brought  about  extinction  in  such  forms  as  the  raptors  and 
the  scratchers.  Ten  of  the  fifteen  extinct  species  recorded  from 
Fossil  Lake  belong  to  genera  which  are  at  present  non-migratory 
in  the  region. 

Whether  or  not  these  genera  were  migratory  during  Pleisto- 
cene time  is,  of  course,  a  matter  of  pure  conjecture.  Allen40 
suggests  that  it  was  during  the  Glacial  Epoch  that  the  migratory 
instinct  was  indelibly  impressed  upon  birds  by  the  pronounced 
seasonal  contrast  prevailing  at  that  time.  Whether  the  instinct 
was  at  that  time  incipient  or  real,  it  seems  proper  to  conclude 
that  those  genera  which  now  display  it  are  the  ones  which  would 
have  profited  by  its  initial  operation  and  have  escaped  extinction. 

There  presents  itself,  then,  the  very  potent  suggestion  that 
the  relatively  small  proportion  of  extinct  forms  represented  in 
the  Fossil  Lake  horizon  is  due  to  the  fact  that  many  of  the 
genera  there  represented  possessed  or  else  developed  the  migra- 
tory instinct  and  were  preserved  except  as  influenced  by  other 
factors. 

The  remaining  four  horizons  may  more  properly  be  com- 
pared as  to  age  upon  the  basis  of  percentage  of  surviving  species, 
and  such  comparison  bears  out  the  conclusions  reached  by  Os- 
born  in  his  study  of  the  mammals. 

Causes  of  Extinction  of  Birds. — After  a  consideration  of  the 
varied  and  in  many  respects  remarkable  avifauna  of  Pleistocene 
times,  it  is  natural  that  the  causes  of  extinction  of  these  forms 
should  hold  an  important  place  in  our  attention.  Why  should 
we  now  have  but  two  eagles  in  southern  California  where  five 
once  flourished?  Why  does  but  one  condor  remain  of  the  five 
species  found  fossil  ?  The  large  phase  of  the  variable  Pleistocene 
Haliaetus  has  withdrawn  toward  the  north  into  British  Col- 
umbia and  Alaska,  while  Phoenicopterus,  the  ciconids,  Polyborus 
and  the  morphnine  eagles  have  withdrawn  to  the  southward. 

The  gigantic  Teratornis  disappeared,  leaving  no  near  relative 


40  Allen,    J.    A.,    The    geography    and    distribution    of    birds,    Auk,    vol. 
10,  No.  2,  Apr.  1893. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  109 

to  represent  the  family  among  the  Catharti formes.  How  late 
did  this  great  bird  persist,  and  did  that  important  factor,  man, 
have  anything  to  do  with  his  disappearance?  According  to  Dr. 
C.  Hart  Merriam,41  the  Me-wah  Indians  of  California  have  a 
legend  concerning  a  gigantic  vulture,  Yel-lo-kin,  so  large  that 
he  was  able  to  capture  the  condor  and  carry  him  up  through  a 
hole  in  the  sky.  The  bird  myths  of  these  Indians  indicate  a  close 
acquaintance  with  the  California  species.  It  may  be  that  Tera- 
tornis  persisted  until  the  arrival  of  man  upon  the  scene,  and  thus 
gave  rise  to  the  Mew-wah  Indian  myth  of  Yel-lo-kin. 

Granting  the  possible  truth  of  such  an  assumption  as  the  con- 
temporaneity of  man  and  Teratornis,  the  primitive  human  animal 
could  have  had  but  little  cause  to  direct  his  efforts  against  the 
large  raptorial  birds.  His  meagre  offensive  armament  would 
probably  have  availed  him  but  little  in  any  event.  Thus  the 
only  influence  he  would  have  been  likely  to  exert  would  be  but 
the  indirect  effect  through  the  extermination  of  large  mammals. 
The  possibility  of  man's  having  exerted  any  such  influence  on 
the  lives  of  avian  species  seems  remote,  in  view  of  the  negative 
evidence  afforded  by  the  absence  thus  far  of  human  remains 
from  western  horizons  of  undoubted  Pleistocene  age. 

Direct  extermination,  or  the  sharpening  of  competition,  by 
incursions  of  Old  World  forms,  is  a  theory  without  the  support 
of  any  tangible  evidence  in  the  case  of  birds.  The  procyonids 
and  Didelphys  are  of  long  standing  in  America.  Felines  would 
greatly  influence  the  larger  birds  by  direct  attack  either  upon 
the  bird  or  its  nest.  It  seems  highly  improbable,  then,  that 
birds  could  have  been  directly  influenced  by  man  or  the  other 
mammals,  but  that  the  chief  relation  of  mammals  to  the  large 
birds  was  in  the  dependence  of  the  latter  upon  the  former  for 
food-supply. 

As  has  been  pointed  out  in  an  earlier  paper,42  the  large  rap- 
torial birds  depended  in  a  dual  respect  upon  the  large  mammals. 
First,  these  birds  fed  upon  the  bodies  of  either  carnivores  or 
herbivores  dying  of  whatever  cause ;  second,  the  vulture  fed  upon 
the  rejected  portion  of  the  carnivore's  kill.  Thus,  any  factor 


41  Merriam,  C.  H.,  The  Dawn  of  the  World,  p.  163,  1910. 

42  Miller,  L.  H.,  Univ.  Calif.  Publ.,  Bull.  Dept.  Geol.,  vol.  6,  p.  2,  1910. 


110         University  of  California  Publications  in  Geology     [ VoL-  7 

which  tended  to  reduce  the  numbers  of  either  group  of  mam- 
mals must  have  reacted  also  upon  the  large  birds  of  prey. 

It  is  not  at  all  improbable  that  the  things  which  brought 
about  the  extinction  of  Pleistocene  mammals  were  also  directly 
operative  in  bringing  about  the  extinction  of  many  species  of 
birds.  Non-raptorial  birds,  except  where  migratory,  would  re- 
spond to  climatic  changes  very  much  as  did  mammals.  Osborn 
makes  suggestions  regarding  the  mammals  as  follows: 

' '  the  Glacial  period  in  North  America  originated  certain  new  con- 
ditions of  life  which  directly  or  indirectly  resulted  in  extinction. 

"These  conditions  include  diminished  herds,  enforced  migrations,  the 
possible  overcrowding  of  certain  southerly  areas,  changed  conditions  of 
feeding,  disturbance  in  the  period  of  mating  and  reproduction,  new  rela- 
tions with  various  enemies,  aridity,  deforestation;  in  short,  a  host  of 
indirect  causes. '  '43 

Disease,  in  all  probability  a  factor  in  the  extinction  of  some 
mammals,  may  likewise  have  been  the  determining  influence  in 
the  case  of  certain  birds.  During  the  winter  of  1908-9  in  south- 
ern California,  the  bodies  of  thousands  of  sea-birds  were  cast 
up  on  the  beach  within  a  comparatively  short  time.  Many  of 
these  specimens  were  examined  by  Dr.  F.  C.  Clark  of  Los  An- 
geles and  by  the  author.  The  intestines  were  found  filled  with 
tape-worms.  Mildness  of  the  weather  coupled  with  the  profound 
emaciation  of  the  birds  indicated  that  death  was  not  due  to 
violence  or  sudden  cause.  While  the  presence  of  parasites  may 
not  have  been  the  only  influence  leading  to  death,  it  was,  in  all 
probability,  an  important  and  possibly  the  determining  factor. 

If,  as  is  so  variously  suggested,  the  rainfall  is  now  much 
less  than  it  was  during  the  Pleistocene,  the  influence  upon  bird 
life  may  have  been  effective  over  wide  areas  through  the  several 
factors  of  food,  shelter  and  nesting  sites.  Pavo  and  Meleagris, 
although  not  always  confined  to  wooded  country,  are  both  forms 
which  might  have  been  strongly  influenced  by  deforestation. 
The  morphnine  eagles,  with  the  possible  exception  of  Geranoae- 
tus,  are  forest-dwelling  birds.  The  local  extinction  of  these  birds 
in  California  may  have  resulted  from  a  thinning-out  of  the 
forests. 


43  Qsborn,  H.  F.,  The  Age  of  Mammals  (New  York,  Macmillan,  1910). 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  111 

Development  of  gigantic  size  in  the  cathartids  is  in  effect 
a  case  of  over-specialization  in  that  it  works  frequently  to  the 
detriment  of  the  species.  The  condors  of  today  are  of  such 
unwieldy  size  that,  after  a  full  meal,  they  experience  much  diffi- 
culty in  taking  wing  from  low  ground.  This  fact  is  reported 
to  have  caused  the  destruction  of  many  individuals  which  had 
been  led  to  alight  in  places  from  which  they  could  not  rise  again 
into  the  air.  Teratornis  must  have  attained  a  bulk  almost  thrice 
that  of  the  condor  if  we  may  judge  from  coracoid  and  furcula. 
The  suggestion  conveyed  by  the  sternum  is  that  the  pectoral 
muscles  were  not  so  heavy  in  proportion,  yet  the  weight  of  the 
bird  must  have  been  far  greater  than  that  of  the  condors.  The 
nature  of  its  food  was  such  that  it  must  have  come  to  the  ground 
to  feed.  The  effort  to  rise  again,  gorged  with  food,  must  have 
been  a  severe  tax  upon  its  strength,  and  slowness  in  taking  wing 
may  have  subjected  it  to  frequent  danger.  The  high,  compressed 
beak  of  Teratornis  resembling  the  eagle's  in  form,  though  struc- 
turally cathartine,  indicated  the  extreme  of  specialization.  The 
large  body  size,  likewise  a  phase  of  specialization,  may  have  mili- 
tated in  the  end  against  the  life  of  the  species. 

The  principle  of  specific  decay  or  senility  of  species  as  a 
cause  of  extinction  may  have  suffered  somewhat  through  the  too 
frequent  application  of  it  by  the  palaeontologist,  yet  there  often 
appear  cases  in  which  no  other  factor  seems  adequate  to  explain 
the  loss  of  a  species.  Certainly  the  intersterility  of  species  would 
lead  to  inbreeding  with  its  attendant  ill  effects.  Incipient  strains 
of  intersterility  within  a  species  might,  where  geographically 
restricted,  lead  to  the  more  rapid  deterioration  of  the  stock; 
generation  upon  generation  of  individuals,  like  the  succeeding 
generations  of  somatic  cells,  become  less  and  less  virile  until  the 
species  would  decline  in  a  manner  comparable  to  the  senile  decay 
of  the  individual.  The  rapid  decline  of  certain  of  the  less  con- 
spicuous species  of  Hawaiian  birds,  such  as  Palmeria  and  Chae- 
toptila,  seems  almost  of  necessity  the  result  of  such  depleting 
influence.  How  effective  this  factor  was  in  robbing  us  of  many 
Pleistocene  birds  it  is  of  course  impossible  to  estimate;  it  would 
seem  proper,  however,  to  look  upon  it  as  possibly  a  contributing 
cause. 


112         University  of  California  Publications  in  Geology     [VOL.  7 

TABULAR  ARRANGEMENT  OF  WEST-AMERICAN  PLEISTOCENE 
AVIFAUNAS 


^Echmophorus  lucasi  Miller  ............................................     * 

^chmorphorus  occidentalis  (Lawrence  ........................ 

Colymbus  holboelli  (Eeinhardt)  ........................................     * 

Colymbus  auritus  Linnaeus  ..............................................     * 

Colybus  nigricollis  californicus  (Heermann)  ..............     * 

Podilymbus  podiceps    (Linnaeus)    ..................................     * 

Larus  argentatus   Pontoppidan   ......................................     * 

Larus  robustus  Shufeldt  ..................................................     * 

Larus  californicus  Lawrence  ............................................     * 

Larus   oregonus   Shufeldt    ................................................     * 

Larus  Philadelphia  (Ord)  ................................................     * 

Xema  sabini   (J.  Sabine)    ................................................     * 

Sterna  elegans  Gambel  ....................................................     * 

Sterna  forsteri  Nuttall  ....................................................     * 

Hydrochelidon  nigra  surinamensis  (Gmelin)   ................     * 

Phalacrocorax  macropus  (Cope)  ........................  ............ 

Pelecanus  erythrorhynchos  Gmelin   ................................     * 

Lophodytes  cucullatus  (Linnaeus)  ..................................     * 

Anas  platyrhynchos  Linnaeus  ...............  .  .......................... 

Chaulelasmus  streperus  (Linnaeus)  ..............  -.  .................     * 

Mareca  americana  (Gmelin)   ............................................ 

Nettion  carolinense  (Gmelin)   ..........................................     * 

Querquedula  discors    (Linnaeus)    ....................................     * 

Querquedula  cyanoptera   (Vieillot)    ................................ 

Spatula  clypeata   (Linnaeus)    ..........................................     * 

Dafila  acuta    (Linnaeus)    .................................................. 

Aix  sponsa  (Linnaeus)  ...................................................... 

Marila  valisineria  (Wilson)  ............................................     * 

Clangula  islandica    (Gmelin)    .......................................... 

Harelda  hyemalis  (Linnaeus)   .............................  •.  ............     * 

Erismatura  jamaicensis   (Gmelin)   .................................. 

Anser   condoni   Shufeldt    ..................................................     * 

Anser  albifrons  gambeli  Hartlaub  ..................................  ? 

Branta  hypsibata  (Cope)   ................................................ 

Branta   canadensis    (Linnaeus)    ...................................... 

Branta   propinqua   Shufeldt   ............................................     * 

Chen   hyperboreus    (Pallas)    ............................................ 

Olor  paloregonus  (Cope)   ..................................................     * 

Indeterminate   anserine   .................................................... 

Indeterminate   anserine   .. 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  113 


»•          fS        -M          fc          C 

.73       o       o>       ?       r 
ca      c     £      S 

IJ2   1  jS 

Pi      H     M.    OR     fM 

Indeterminate   anserine    

Phoenicopterus  copei  Shufeldt  * 

Ciconia  maltha  Miller  

Jabiru    mycteria    (Lichtenstein)    

Mycteria  americana  Linnaeus  

Ardea  herodias  Linnaeus  

Ardea  paloccidentalis   Shufeldt   * 

Grus  minor  Miller  

Grus  canadensis   (Linnaeus)   

Fulica   americana  Gmelin   

Fulica  minor  Shufeldt  * 

Lobipes  lobatus   (Linnaeus)    * 

Oreortyx  picta  (Douglas)  

Lophortyx  californica  (Shaw)  

Lophortyx,  sp 

Dendragapus   obscurus    (Say)    

Bonasa  umbellus  (Linnaeus)  .'. 

Tympanuchus  pallidicinctus  (Eidgway)   * 

Pedioecetes  phasianellus  columbianus    (Ord)    * 

Pedioecetes  lucasi  Shufeldt  * 

Pedioecetes  nanus  Shufeldt  

Palaeotetrix  gilli  Shufeldt   * 

Indeterminate   odontophorid   

Meleagris,    sp 

Pavo  californicus  Miller  

Gymnogyps  californianus  (Shaw)  7 ... 

Gymnogyps  amplus  Miller  

Sarcorhamphus  clarki  Miller  

Cathartornis  gracilis  Miller   

Pleistogyps  rex  Miller  

Cathartes  aura  (Linnaeus)   

Catharista  occidentalis  Miller  

Catharista  shastensis  Miller  

Teratornis  merriami  Miller  

Elanus  leucurus    (Vieillot)    

Circus  hudsonius    (Linnaeus)    

Circus,    sp 

Accipiter  velox  (Wilson)  

Buteo  borealis   (Gmelin)   

Buteo  swainsoni  Bonaparte  (?)   

Buteo,  sp - 

Archibuteo  ferrugineus   (Lichtenstein)   

Aquila  chrysaetos  (Linnaeus)  -~. 


114         University  of  California  Publications  in  Geology     [VOL.  7 


3  J  I  5 

£  I  *  1 

fill 

fa        Pi      P-i        02 

Aquila  pliogryps  Shufeldt  * 

Aquila  sodalis  Shufeldt  * 

Haliaetus  leucocephalus   (Linnaeus)    

Morphnus  woodwardi  Miller  * 

Geranoaetus  melanoleucus  Auct.  (?)  

Geranoaetus  grinnelli  Miller  * 

Geranoaetus   fragilis   Miller   * 

Falco  peregrinus  Tunstall  

Falco,  sp * 

Falco  sparverius  Linnaeus  

Polyborus  tharus  Auct * 

Aluco  pratincola   (Bonaparte) 

Asio  wilsonianus  (Lesson)   

Asio  flammeus   (Pontoppidan)    

Otus  asio  (Linnaeus)   

Bubo  virginianus  (Gmelin)   

Bubo  sinclairi  Miller  *     * 

Speotyto  cunicularia  hypogaea  (Bonaparte)   

Glaucidium  gnoma  Wagler  

Micropallas  whitneyi  (J.  G.  Cooper)  

Neomorpha   ?,  sp 

Colaptes  cafer  (Gmelin)  

Otocoris  alpestris  (Linnaeus)   

Cyanocitta  stelleri  (Gmelin)  

Corvus  corax  Linnaeus  

Corvus  brachyrhynchos  Brehm  

Corvus  annectens  Shufeldt  * 

Corvus,   sp 

Xanthocephalus  xanthocephalus   (Bonaparte)   

Agelaius  gubernator  (Wagler)  

Sturnella  neglecta  Audubon  

Euphagus  cyanocephalus  (Wagler)  

Euphagus  affinis  Shufeldt  * 

Pipilo,    sp 

Lanius  ludovicianus  Linnaeus  ...  * 


1912]  Miller:  Pacific  Coast  Avian  Palaeontology  115 

BIBLIOGRAPHY  OF  PACIFIC  COAST  FOSSIL/  AVIFAUNAS 

1878.  Cope,  E.  D.,  Bull.  U.  S.  Geol.  Surv.  Terr,  iv  no.  2,  May  3,  1878. 
Describes  three  species  of  birds  from  Fossil  Lake,  Ore. 

1892.  Shufeldt,  E.  W.,  A  Study  of  the  Fossil  Avifauna  of  the  Equus 
Beds  of  the  Oregon  Desert,  Journ.  Acad.  Nat.  Sci.  Phila.  no.  9, 
p.  389. 

1894.  Cope,  E.  D.,  On  Cyphornis,  an  Extinct  Genus  of  Birds,  Journ.  Acad. 
Nat.  Sci.  Phila.  no.  9,  p.  449. 

1901.  Lucas,  F.  A.,  A.  Flightless  Auk,  Mancalla  californiensis,  from  the 
Miocene  of  California,  Proc.  U.  S. -Nat.  Musv  vol.  24;  p.  133. 

1909.  Miller,  L.  H.,  Pavo  californicus,  a  Fossil  Peacock  from  the  Quater- 
nary Asphalt  Beds  of  Eancho  La  Bre£^  Univ.  Calif.  Publ.,  Bull. 
Dept.  Geol.,  vol.  5,  p.  285. 

1909.  Miller,   L.    H.,    Teratornis,   a    New   Avian    Genus    from   Eancho    La 

Brea,  Univ.  Calif.  Publ.  Bull.  Dept.  Geol.,  vol.  5,  p.  305. 

1910.  Miller,    L.    H.,    Wading    Birds    from    the    Quaternary    Asphalt    of 

Eancho  La  Brea,  Univ.  Calif.  Publ.  Bull.  Dept.  Geol.,  vol.  5,  p. 
437. 

1910.  Miller,  L.  H.,   The  Condor-like  Vultures  of  Eancho  La  Brea,  Univ. 

Calif.  Publ.  Bull.  Dept.  Geol.,  vol.  6,  p.  1. 

1911.  Miller,  L.  H.,  Additions  to  the  Avifauna  of  the  Pleistocene  Deposits 

at  Fossil  Lake,  Oregon,  Univ.  Calif.  Publ.  Bull.  Dept.  Geol.,  vol. 

6,  p.   79. 
1911.     Miller,    L.    H.,    A    Series   of   Eagle    Tarsi    from    the   Pleistocene    of 

Eancho  La  Brea,  Univ.  Calif.  Publ.  Bull.  Dept.  Geol.,  vol.  6,  p.  305. 
1911.     Miller,  L.   H.,  Avifauna  of  the  Pleistocene  Cave  Deposits  of  Cali- 
fornia, Univ.  Calif.  Publ.,  Bull.  Dept.  Geol.,  vol.  6,  p.  385. 


NOTE. — Since  the  text  of  this  paper  went  to  press,  bird  remains  have 
been  found  in  the  Upper  San  Pedro  Pleistocene  at  San  Pedro,  Cal.,  by 
Dr.  F.  C.  Clark  of  Los  Angeles.  These  remains  were  very  generously 
presented  to  the  present  writer  by  Dr.  Clark,  and  by  permission  of  the 
latter,  were  deposited  in  the  Vertebrate  Palaeontology  Collections  at  the 
University  of  California.  Three  of  the  specimens  are  almost  perfect,  the 
several  others  are  too  fragmentary  for  determination.  One  specimen  repre- 
sents an  undescribed  species  of  grebe  of  the  genus  ^chmophorus  but  in  view 
of  the  fact  that  the  active  exploration  of  these  beds  now  going  on  will 
possibly  bring  to  light  other  remains  of  like  nature,  a  description  of  the 
species  is  thought  unwise  at  present. 

Eemains  of  Bison,  Equus,  a  camelid,  rodents,  seals,  small  turtles,  and 
sting  rays  have  also  been  taken  from  these  beds  by  Dr.  Clark  and  the 

writer. 

* 

LIST  OF  SPECIES  FROM  UPPER  SAN  PEDRO 

Mammals  Birds 

Equus  ^chmophorus,  n.  sp. 

Bison  Nettion  carolinense  (Gmelin) 

Camelid  Sturnella  neglecta  Audubon 


VOLUME  4. 

PBICK 

1.  The  Geology  of  the  Upper  Region  of  the  Main  Walker  River.  Nevada,  by  Dwight 

Smith  I..; ."....     aoc 

Primitive  Ichthyosaurian  Limb  from  the  Middle  Triassic  of  Nevada,  by  John 

Merriam   ." lOc 

3.  Geological  Section  of  the  Coast  Ranges  North  of  the  Bay  of  San  Francisco,   by 

V.  C.  Osmont  „ 40c 

4.  Areas  of  the  California  Neocene,  by  Vance  C.  Osmont. .r loc 

ntribution  to  the  Palaeontology  of  the  Martinez  Group,  by  Charles  E.  Weaver 
;  w  or  Imperfectly  Known  Rodents  and  Ungulates  from  the  John  Day  Series,  by 

William  J.  Sinclair  .'..     2oe 

".   Xew  Mammalia  from  the  Quaternary  Caves  of  California,  by  William  J.  Sinclair     25c 

8.  Preptoceras.  a  New  Ungulate  from  the  Samwel  Cave.  California,  by  Eustace  L. 

Furlong     lOc 

9.  A  New  Sabre-tooth  from  California,  by  John  C.  Merriam  .  5c 

10.  The  Structure  and  Genesis  of  the  Comstoek  Lode,  by  John  A.  Reid 15c 

11.  The  Differential  Thermal  Conductivities  of  Certain  Schists,  by  Paul  Thelen.. 

etch  of  the  Geology  of  Mineral  King.  California,  by  A.  Knopf  and  P.  Thelen 35c 

13.  Cold  Water  Belt  Along  the  West  Coast  of  the  United  States,  by  Ruliff  S.  Holway 

14.  The  Copper  Deposits  of  the   Robinson   Mining  I  Nevada,   by   Andrew   C. 

Lawson      50c 

15.  I.  Contribution  to  the  Classification  of  the  Amphiboles. 

II.  On  Some  Glaucophane  Schists,  Syen.  by  G.  Murgoo.  35c 

16.  The  Geomorphic  Features  of  the  Middle  Kern,  by  Andrew  C.  Lawson....  .     loc 

res  on  the  Foothill  Copper  Belt  of  the  Sierra  Nevada,  by  A.  Knopf. 

18.  An  Alteration  of  Coast  Range  Serpentine,  by  A.  Knopf. 

17  and  18  in  one  cover  loc 

19.  The  Geomorphogeny  of  the  Tehachapi  Valley  System,  by  Andrew  C.  Law-  35c 

VOLUME 

1.  Carnivora  from  the  Tertiary   Formations  of  the  John   Day   Region,  by  John  C. 

Merriam      60c 

me   Edentate-like   Remains  from  the  Maseall   Beds  of  Oregon,  by   William  J. 
Sinclair. 

Mollusca  from  the  John  Day  and  Maseall  Beds  of  Oregon,  by  Robert  E.  C. 
Stearns. 

"2  and  3  in  one  cov  loc 

rstraciont  Teeth  from  the  West  American  Tria-  Ina  M.  Wemple lOc 

5.  Preliminary  Note  on  a  New  Marine  Reptile  from  the  Middle  Triassie  of  Nevada, 

by  John  C.  Merriam 10c 

.tes  on  Lawsonite,  X^olumbite,  Beryl,  Barite.  and  Calcite.  by  Arthur  S.  Ea'.de lOc 

California,  with  Supplemer                  :s  on  Other  Species  of 
David  Starr  Jordan 5^c 

8.  Fish  Remains  from  the  Marine  Lower  Triassic  of  Aspen  Ridge.  Idaho,  by  Malcoln. 

Goddard  —      5c 

9.  Benito!-  difornia   Gem   Mineral,   by   George  Davis   Louderback.   with 

Chemical  Analysis  by  Walter  C.  Blasdale  oc 

.tes  on  Quaternary  Felidae  from  California,  by  John  F.  Bovard 

11.  Tertiary  Faunas  of  the  John  Day  Region,  by  John  C.  Merriam  and  William  J. 



iopods  and  Insects  of  California,  by  Fordyce  Grinnell,  Jr lOc 

13.  Notes  on  the  0  >f  the  Thalattosaurian  Genus  Xectosaurus.  by  John  C. 

Merriam      _ 

>tes  on  Some  California  Mineral-  hur  S.  Eakle loc 

tes  on  a  Collection  of  Fossil  Mammals  from  Virgin  Valley,  Nevada,  by  James 

Williams    Gidley    

16.  Stratigraphy  and  Palaeontology  of  the  San  Pablo  Formation  in  Middle  California. 

by  Charles  E.  Weaver  

-w  Echinoids  from  the  Tertiary  of  California,  by  Charles  E.  Weaver  oc 

on  Echinoids  from  the  Tertiary  of  California,  by  R.  W.  Pack 

19.  Pavo  californicus.  a  Fossil  Peacock  from  the  Quaternary  Asphalt  Beds  of  Rancho 
La  Brea.  by  Lcye  Holmes  Miller  


VOLUME  5 — (Continued}. 

PRICE 

20.  The  Skull  and  Dentition  of  an  Extinct  Cat  closely  allied  to  Felis  atrox  Leidy,  by 

John  C.  Merriam   15C 

21.  Teratornis,  a  New  Avian  Genus,  from  Raneho  La  Brea,  by  Loye  Holmes  Miller lOc 

22.  The    Occurrence    of    Strepsicerine    Antelopes    in    the    Tertiary    of    Northwestern 

Nevada,  by  John  C.  Merriam k 10c 

23.  .Benitoite,  Its  Paragenesis  and  Mode  of  Occurrence,  by  George  Davis  Louderbaek, 

with  chemical  analyses  by  Walter  C.  Blasdale 75c 

24.  The  Skull  and  Dentition  of  a  Primitive  Ichthyosaurian  from  the  Middle  Triassic, 

by  John  C.  Merriam 10c 

25.  New  Mammalia  from  Raneho  La  Brea,  by  John  C.  Merriam  5c 

26.  An  Aplodont  Rodent  from  the  Tertiary  of  Nevada,  by  Eustace  L.  Furlong lOc 

27.  Evesthes  jordani,  a  Primitive  Flounder  from  the  Miocene  of  California,  by  James 

Zacchaeus   Gilbert 15c 

28.  The  Probable   Tertiary  Land   Connection  between   Asia   and  North   America,   by 

Adolph  Knopf lOc 

20.  Rodent  Fauna  of  the  Late  Tertiary  Beds  at  Virgin  Valley  and  Thousand  Creek, 

Nevada,  by  Louise  Kellogg  15c 

30.  Wading  Birds  from  the  Quaternary  Asphalt  Beds  of  Raneho  La  Brea,  by  Loye 

Holmes  Miller  , lOc 

VOLUME  6. 

1.  The  Condor-like  Vultures  of  Raneho  La  Brea,  by  Loye  Holmes  Miller 15o 

2.  Tertiary  Mammal  Beds  of   Virgin  Valley  and  Thousand  Creek   in   Northwestern 

Nevada,  by  John  C.  Merriam.     Part  I. — Geologic  History 50c 

3.  The  Geology  of  the  Sargent  Oil  Field,  by  William  F.  Jones  25c 

4.  Additions  to  the  Avifauna  of  the  Pleistocene  Deposits  at  Fossil  Lake,  Oregon,  by 

Loye  Holmes  Miller  lOc 

5.  The  Geomorphogeny  of  the  Sierra  Nevada  Northeast  of  Lake  Tahoe,  by  John  A.  Reid     60c 

6.  Note  on  a  Gigantic  Bear   from  the  Pleistocene  of  Raneho  La  Brea,  by  John  C. 

Merriam. 

7.  A  Collection  of  Mammalian  Remains  from  Tertiary  Beds  on  the  Mohave  Desert, 

by  John  C.  Merriam. 

Nos.  6  and  7  in  one  cover  lOc 

8.  The  Stratigraphic  and  Faunal  Relations  of  the  Martinez  Formation  to  the  Chico 

and  Tejon  North  of  Mount  Diablo,  by  Roy  E.  Dickerson  5c 

9.  Neocolemanite,  a  Variety  of   Colemanite,  and  Howlite  from  Lang,  Los  Angeles 

County,  California,  by  Arthur  S.  Eakle lOc 

10.  A   New  Antelop"  from  the  Pleistocene  of  Raneho  La  Brea,  by  Walter  P.  Taylor       5c 

11.  Tertiary   Mammal   Beds   of   Virgin   Valley  and    Thousand    Creek    in    Northwestern 

Nevada,  by  John  C.  Merriam.     Part  IL— Vertebrate  Faunas  $1.00 

12.  A  Series  of  Eagle  Tarsi  from  the  Pleistocene  of  Raneho  La  Brea,  by  Loye  Holmes 

Miller lOc 

13.  Notes  .on  the  Relationships  of  the  Marine  Saurian  Fauna  Described  from  the  Triassic 

of  Spitzbergen  by  Wiman,  by  John  C.  Merriam. 

14.  Notes  on  the  Dentition  of  Omphalosaurus,  by  John  C.  Merriam  and  Harold  C.  Bryant. 

Nos.  13  and  14  in  one  cover  - — 15c 

15.  Notes  on  the  Later  Cenozoic  History  of  the  Mohave  Desert  Region  in  Southeastern 

California,  by  Charles  Laurence  Baker  50c 

16.  Avifauna  t)f  the  Pleistocene  Cave  Deposits  of  California,  by  Loye  Holmes  Miller  15c 

17.  A  Fossil  Beaver  from  the  Kettleman  Hills,  California,  by  Louise  Kellogg  5c 

18.  Notes  on  the  Genus  Desmostylus  of  Marsh,  by  John  C.  Merriam  lOc 

19.  The  Elastic-Rebound  Theory  of  Earthquakes,  by  Harry  Fielding  Reid  25c 

VOLUME  7. 

1.  The  Minerals  of  Tonopah,  Nevada,  by  Arthur  S.  Eakle  25c 

2.  Pseudostratification  in  Santa  Barbara  County,  California,  by  George  Davis  Louder- 

back   20c 

3.  Recent  Discoveries  of  Carnivora  in  the  Pleistocene  of  Raneho  La  Brea,  by  John  C. 

Merriam    5° 

4.  The  Neocene  Section  at  Kirker  Pass  on  the  North  Side  of  Mount  Diablo,  by  Bruce 

L.   Clark    15c 

5.  Contributions  to  Avian  Palaeontology  from  the  Pacific  Coast  of  North  America,  by 

Loye  Holmes  Miller  60c 


NON-CIRCULATING  BOOK 


244558 


UNIVERS 

10m-l,'28 


ftARY 


